Author: Bubbles

Compared to many other outdoor activities, scuba diving is generally considered a low-risk activity. However, it does involve some inherent dangers for which it requires training and good health. Being aware of the main scuba diving risks is the first in many steps you have to take to prevent harm and practice safe diving.

1. Decompression Sickness

Developing decompression sickness (DCS), or the bends, is one of the most common scuba diving health risks. The term is used to describe an illness that results from a rapid decrease in the pressure surrounding you. It occurs mostly in scuba diving and deep-sea diving because when you dive with compressed air, your body takes in extra oxygen and nitrogen. While your body uses the oxygen, the nitrogen gets dissolved into the blood and remains there during the dive.

As you ascend towards the surface of the water, the water pressure around you decreases. In rapid ascents, the nitrogen does not have time to clear out and forms bubbles in your tissues and bloodstream. These microbubbles can cause damage to your blood vessels and block normal blood flow. Symptoms include joint and muscle pain, loss of hearing, nausea, memory loss, confusion, and uncontrollable shaking, among others.

Although DCS hits randomly, there are a few factors that may put you at higher risk of developing this illness: heart muscle birth defects, low cardiovascular fitness, use of alcohol or tobacco, a high percentage of body fat, old or current injuries, lung disease, diving in cold water, and fatigue. Females and people over the age of 30 are also more at risk, according to Harvard Health Publishing.

There are different levels of DCS, and the symptoms can appear as late as 48 hours after the dive. Some cases can be very serious, even life-threatening. Take the necessary prevention measures before and after each dive and discuss your concerns with your doctor, especially if you suffer from a medical disease or condition.

2. Nitrogen Narcosis

Nitrogen narcosis, or inert gas narcosis/ rapture of the deep/Martini effect, is a temporary condition that affects deep-sea divers that swim past 100 feet (30 meters). The condition is caused by breathing nitrogen at a high partial
pressure.

The partial pressures of oxygen and nitrogen at sea level are around 0.21 atm and 0.78 atm, respectively. Upon descend, the partial pressure of the gases increases. When a diver reaches a depth of about 131 feet (40 meters), the partial pressures of oxygen and nitrogen are about 1.05 atm and 3.9 atm, respectively.

When you inhale the gases at a higher partial pressure, you experience symptoms similar to those of drunkenness. It’s one of the reasons why deep divers require additional training to combat these issues.
Deep-sea divers can also use heliox (a mixture of helium and oxygen) instead, as it has been found that helium does not cause inert gas narcosis .

The symptoms of nitrogen narcosis include a sense of euphoria, disorientation, poor judgment, difficulty concentrating, hallucinations, and others. The condition usually resolves upon ascent, but it may – in some cases – increase the risk of developing other conditions such as DCS. It’s important to learn more about nitrogen narcosis so you can recognize it in yourself and others.

3. Barotrauma

Barotrauma is also among the common health risks scuba diving, and it is caused by the increased underwater pressure. There are different types of barotrauma, including sinus, teeth, and lung barotrauma, but the most common kind experienced by divers is middle-ear (otic) barotrauma. It can cause extreme pain, fluid buildup, bleeding, and even hearing loss.

Middle-ear barotrauma is often experienced by divers who fail to equalize the middle-ear pressure during descent. However, equalization is easily done by using various maneuvers such as swallowing or pinching the nose and blowing. If you cannot, for whatever reason, equalize, it’s best to end the dive.

4. Oxygen Toxicity

Although not among the most common scuba diving risks, oxygen toxicity is a medical condition that can have serious negative effects on the body. Open-circuit, rebreather, and Enriched Air Nitrox (EAN) divers who use mixed gases are exposed to the risk of oxygen toxicity. For most divers, this condition is not an issue, but at extreme depths too much oxygen becomes toxic.

The two types of oxygen toxicity are Central Nervous System Oxygen Toxicity (CNS), and Pulmonary Oxygen Toxicity (POT), the former being more common among divers. When diving extreme depth, it’s important to know what to look for in both yourself and others. Symptoms include convulsions, visual disturbances, nausea, twitching, dizziness, and irritability.

There’s no guarantee oxygen toxicity won’t affect deep divers even with preventive measures, but there are a few things you can do to minimize the risk. Do not exceed your depth limit, use a dive computer for tracking, analyze your gas every time, avoid exhaustion when underwater, and make sure you breathe easily.

5. Air or Gas Embolism

When you ascend too quickly, nitrogen bubbles can form in your tissue and blood. As discussed above, this is called decompression sickness. If those bubbles block a small artery, they can cut off some of the blood supply. Holding your breath can also cause the air in your lungs to expand, which may lead to lung tissue ruptures and arterial gas embolism due to the nitrogen bubbles being released into the arterial circulation.

The symptoms include joint and muscle pain, irregular heartbeat, chest pain, blurred vision, and anxiety, among others. Treatment involves hyperbaric oxygen therapy. Air or gas embolism is among the preventable scuba diving risks; limiting the depth of your dive, making a slow ascent, breathing normally, and not diving with a cold are among the many prevention measures you can take.

6. Running Out of Breathing Gas

Running out of breathing gas is a common scuba diving risk, especially among divers that lack training or inexperienced divers, as it often occurs due to poor gas management. It may also happen because of equipment failure and unforeseen exertion.

You must understand how much breathing gas you need for a particular dive, know how to calculate the limits of available gas, monitor the remaining gas, and ascend to the surface with enough breathing gas in your tank.

Air is the most common breathing gas used in scuba diving. If you’re not a commercial diver, tech diver or practicing other forms of advanced diving, chances are you’ll be diving on air supply. In this case, it’s advised to ascend with about 50 Bar (500 PSI) of breathing gas remaining in your tank.

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7. Hypothermia

When diving in cold water, hypothermia is one of the common diving risks. Nonetheless, it can occur even in warm tropical waters because the water you dive in is almost always colder than the temperature of your body. Furthermore, water draws heat away from our bodies about 20 times faster than air, so it’s possible to develop mild hypothermia in most waters. It’s important to know the signs of hypothermia and ascend before it settles in.

Preventing hypothermia requires preparation; divers need to understand what type of protective garments they need for each specific dive and how to properly use it in order to conserve their body heat. Be prepared by undergoing training so you can be ready to act in case of a rescue/self-rescue.

8. Unsafe Marine Life Encounters

As you dive into the water, you’re entering untamed wilderness which you may know little about. Most creatures are not harmful or aggressive, but some may react in unpredictable ways if they feel threatened. Remember, it’s their home – not yours – you’re entering. Every diver should know not to touch or get too close to wildlife; it’s part of the diver etiquette.

Staying within a safe distance from both underwater fauna and flora not only ensures you’re not hurting them but also keeps you safe from any possible harm. Some animals bite while others secrete poison; even corals can cause stings and lacerations. Pay attention to your surroundings at all times and treat marine life with respect to avoid these scuba diving risks.

9. Malfunctioning Equipment

Defective equipment is yet another scuba diving risk. Some of the common equipment failures involve O-ring failure, rupture of a regulator hose, closing and jamming of the cylinder valve.

Always check the equipment for design flaws, tears, and functional issues before each dive. If you suspect your equipment may not be functioning correctly, ask for a new one. If you own your equipment, use it properly and perform maintenance.

10. Entrapment and Entanglement

According to Divers Alert Network, entrapment and entanglement are triggers in approximately 20 percent of fatal dive accidents. They are common factors in fatalities involving asphyxia. When you’re diving in an overhead environment with no direct, vertical access to the surface, all scuba diving risks are inherently higher.

Divers who wish to dive caves, caverns, wrecks or swim under ice should go through appropriate training. You’ll need to learn how to thoroughly plan your dive, use special equipment, and never dive alone. Entrapment can be prevented only by avoiding overhead environments – at least until properly trained, while fatal entanglement can be prevented by carrying a dive knife.

11. Getting Lost/Separated from the Group

Getting lost at sea or separated from your buddies can be a scary feeling. It may occur because you or your buddy wandered off in search of some interesting creature or were left behind by your dive boat (less likely, but it’s been known to happen). In case of emergency, the boat may need to leave quickly and leave behind some of the other divers.

The captain of the boat should brief divers on what to do if they don’t find the boat when they surface. If you’re not briefed on the matter, as it may sometimes happen, you should ask about the plan of action yourself.
Another boat should already be on its way to retrieve the stranded divers. Discuss the procedures for unlikely events with the captain, dive guide or instructor, and carry safety and signaling devices to be prepared for anything.

Always remain near the group, never dive alone even if you are an experienced diver, and go over the different scenarios that may occur with the boat crew and your buddies. It’s good to have a plan of action so you know what to do in case you ever get separated or left behind.

12. Drowning

The most common cause of diving fatalities is drowning, and this is because the victim dies in the water. Drowning while diving generally occurs due to some of the other risks described above or a medical condition. In fact, the cause of many drowning fatalities has been found to be a heart attack, generally triggered by a pre-existing pathology in the diver.

Equipment malfunction, gas-supply problems, and rough water are also triggers that can lead to drowning incidents. Proper training and a good buddy system can go a long way in preventing drowning. Regular checkups with your doctor should help you treat and manage many of the conditions that can cause incapacitation.

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13. Overpowering Currents

Currents can be some of the most physically demanding and unpredictable obstacles a scuba diver can encounter during a dive. Strong currents can cause rapid air depletion, accelerated gas loading, exhaustion, and separation, among others. They can even prevent you from returning to the boat.

Those diving in strong currents, especially drift divers, need to have a good understanding of how currents work. Surface currents do not necessarily travel in the same direction as bottom currents, for example. Some can also reverse direction during a dive. Make sure you’re properly trained to dive difficult sites and have a plan in place.

14. Salt Water Aspiration

Another risk of scuba diving is salt water aspiration, a rare disorder suffered by those who inhale a mist of seawater. This is due to faulty equipment or poor diving technique but may also occur in near-drownings. Diagnosing sea water aspiration may prove difficult because the symptoms mimic those of decompression sickness and near-drowning.

Sea water aspiration has damaging effects on the diver’s lungs. Inhaling salt water can cause bodily fluids to move from your lungs to your breathing spaces, making breathing difficult or impossible. Most divers have mild reactions to salt water and resolve within a few hours. Some divers, however, have severe reactions and should seek immediate help if they suspect they may suffer from salt water aspiration.

15. Displacing the Second Stage

Although unlikely, having your second stage regulator displaced from your mouth can happen. This usually occurs when another diver accidentally pulls it from your mouth, gets entangled in kelp, gets knocked out by impact, you lose consciousness and release grip or when you displace it with your own arm movement.

Regulator recovery is a skill taught in diving school, so as long as you don’t panic you should be able to easily recover your second stage. Your diving buddy can help too, so make sure to signal them. In the meantime, it’s important to exhale continuously and not hold your breath.

16. Caustic Cocktail

One of the scuba diving risks affecting rebreathers is exposure to a caustic cocktail. This happens when the absorbent material used to remove carbon dioxide from the breathing gas is inundated with water. The contaminated water can move along the breathing loop and into the diver’s mouth. The caustic cocktail can cause choking and even caustic corrosion of the mucous membranes.

It’s important to always check your rebreather for leaks before each dive and close the surface valve when it’s not in your mouth. If the caustic cocktail enters your mouth, rinse your mouth and switch to an alternative gas supply before returning to the surface.

17. Being Hit by a Boat

Boat-propeller strikes cause hundreds of injuries and dozens of deaths in people engaging in water activities in the U.S. alone. The risk of accidents is higher for popular destinations that often have multiple boatloads of divers at the same dive site. Even the propeller of a small boat can cause a serious, even fatal injury.

Preventing accidents, especially in areas with a lot of boat traffic, requires divers and boaters to be constantly aware of their surroundings before making the ascent. Accidents can be avoided as long as both parties follow a set of key rules and have an emergency action plan set up.

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18. Dysbaric Osteonecrosis

Dysbaric osteonecrosis (DON) is an avascular bone necrosis developed by those exposed to changes in pressure. More common among professional divers than recreational ones, it mostly affects compressed-air workers. For divers, the prevalence is higher for divemasters than others.

This bone necrosis is often associated with decompression sickness, although a clear correlation between the two has yet to be established. It is likelier that there are predisposing factors more dependent on variables related to high pressure that contribute to the development of DON.

Technical divers and those that regularly dive deeper than 100 feet (30 meters) are recommended to do a long bone survey every few years. This is also the case for those who regularly perform inadequate decompression.

Have you ever found yourself in a dangerous situation while diving? Leave us a comment below and tell us about the scuba diving risks you faced and how you overcame them.

Scuba diving is an increasingly popular hobby for people all around the world. While it is a generally safe activity when conducted correctly, it does entail a few risks. Luckily, these dangers are almost always preventable as long as you follow some vital scuba diving safety rules.

Disclaimer: The information offered below is designed for educational purposes only. Do not rely solely on this information; seek professional advice on all matters related to scuba diving safety. If you have any further concerns or questions, consult with your guide, divemaster or diving instructor.

Scuba Diving Safety Before Your Dive

1. Get Certified and Master Skills

Scuba diving involves risks, which is why it requires special training. The instruction uses a curriculum developed by recognized diving agencies; divers learn about the principles of diving and develop skills by diving in both confined and open water environments. The safety-related information is brought in stages, and divers will learn about the specific risks of each diving level they wish to obtain and how to tackle them.

Learning how to use your buddy’s alternate air source, conduct a Controlled Emergency Swimming Ascent (CESA), disconnect your pressure inflator hose, clear your mask, perform CPR, and give emergency oxygen are among the vital scuba diving safety skills you should learn and master.

2. Stay Healthy

One of the most ignored safety checks before a dive is ensuring you’re in a healthy state. So what should divers do for their own safety?
Here are a few things you should and shouldn’t do:

• Don’t drink. Drinking before a dive entails a number of risks, including nitrogen narcosis, heat loss, impaired judgment, and it affects the reaction time, attention span, and visual tracking, among others.
• Don’t smoke. It’s advisable to abstain from smoking at least 12 hours before your dive. If you’re doing multiple dives that day, do not smoke between dives. Smoking before a dive results in reduced tissue oxygenation, causing the body not to function at peak level. 
• Workout. When diving, you’re putting your body through intense pressure. Improved physical fitness helps your body carry oxygen and boosts circulation, reducing susceptibility to decompression sickness (DCS). Even working out 24 hours before your dive can help prevent the risk of DCS.
• Get medically assessed. Some medical conditions are not compatible with diving, so it’s recommended to get yourself checked periodically to ensure you’re in top-notch condition. Even a common cold or sinus infection can prevent you from going under.

3. Learn About Your Dive Site(s)

Depending on the place you’re diving in, the scuba diving safety measures differ – from the gear you should bring and use to the hours it’s most safe to dive during. Check the weather and ask the local dive center about the water conditions, currents, visibility, and wildlife you may encounter. It’s also important to learn about the on-site facilities and ensure you’ll have access to emergency equipment.

4. Buy Your Own Gear

If you’re serious about scuba diving and plan to dive often, investing in your own gear is one of those things that contribute to your safety. Your gear will fit just right, you’ll become familiarized with it and you’ll always know how to use it safely, allowing you to focus more on your dive. You may not want to buy your own tank and carry it overseas just yet, but things like wetsuits, dive computers, regulators and the likes are easier to bring along.

5. Double Check Your Gear

Whether you own your gear or rent it, always do a safety check before your dives. Inspect it for wear and tear; look for faulty zippers, cracked buckles, and straps, or frayed areas that could lead to leaks. Your regulator and tank should also get checked regularly for functional issues.

6. Know Your Limits

Divers should always dive within their limits. If you haven’t yet gained the required set of skills for a specific type of dive or if you’re not feeling mentally and physically capable to dive, don’t do it. It’s no shame in canceling a dive or changing the dive site with one you’re more comfortable diving. 

Ethical dive centers will not allow you to dive a site that’s beyond your qualification level, but you must also be aware of the importance of sticking to what you know. Your dives should match your training and experience.

7. Bring a Buddy (and Be a Good Buddy)

One of the best scuba diving safety measures is to dive with a partner. All divers should be capable of taking care of themselves, but it sure doesn’t hurt to have another pair of eyes and hands, and an extra regulator in case of an emergency.

There are many situations underwater that can be easily fixed when you work in pairs, but only as long as you are within eyesight of your diving partner.

8. Learn Dive Signals

When you are underwater, talking is obviously not an option so you need another method of communication that will allow you to “talk” to other divers. There are a number of different hand signals you can use, from directional to the important safety signals. It’s imperative both you and the other divers know the safety signals so you can understand each other.

9. Plan Your Dive and Dive Your Plan

Planning your dive is yet another scuba diving safety rule you should follow. Prior to going underwater, you and your diving partner(s) should decide on the maximum depth you will go, the bottom time, and agree on the hand signals, among others.

Planning a dive is something both new and experienced divers learn in diving school. There are plenty of tools you can use to plan your dive, from dive computers and timing devices to a recreational dive planner.

You should listen to briefings from your guide, as they’ll discuss information related to the general dive plan. Once you have a solid plan, you should stick to it and not give in to the temptation of diving deeper or straying from the group.

10. Purchase a Scuba Diving/Travel Insurance

You can never be too sure everything will go according to plan on your diving trip. Going to the hospital in a foreign country can be extremely costly, especially if you’ll ever need to use a decompression chamber. Investing in a good scuba diving insurance or a travel insurance that covers injuries that occur from practicing this sport can save you a lot of money in medical bills.

An interesting fact about insurances: Did you know that an insurance does not cover divers that are not certified or those that are diving to a depth past their certification level?

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Scuba Diving Safety During Your Dive

11. Don’t Hold Your Breath

One of the main scuba diving safety rules is to always breathe. Divers are often tempted to hold their breath underwater, but it can be extremely dangerous to do so.
The deeper you go, the higher the water pressure gets, and the volume of the lungs goes down. When you ascend, the lungs expand, and that’s when the air in your lungs become unsafe.

If you hold your breath during ascent, your lungs and the air inside them will expand as the water pressure drops. Because that air has nowhere to escape, it will swell against the walls of the lungs. This can cause tears, lung collapse, air embolism, and puts too much pressure on the heart, which can be fatal.

12. Do Safety Stops

You’d think something containing the word “safety” would be required, right? In fact, some safety stops are optional unless you’re diving deeper than 30 meters (100 feet). However, they’re highly recommended for all dives, including shallower ones.

A safety stop is a 3 to 5 minute stop conducted between 5 to 6 meters (15 to 20 feet) during ascent. These stops allow the absorbed nitrogen to be released from a diver’s body. After completing the safety stop, it’s important to rise slowly to the surface and maintain a speed of no more than 18 meters (60 feet) per minute.

13. Do Decompression Stops

Decompression stops are generally scheduled according to how long and how deep you dive. The deeper a diver goes and the longer they stay underwater, the more decompression stops need to be accomplished.

The reason why decompression stops are considered a requirement is because the greater the depth, the more nitrogen is absorbed by the diver’s body. During ascent, the nitrogen accumulated during the dive returns to the blood in the form of microbubbles and is then rejected by the lungs during expiration. Decompression stops allow for gradual recovery, ensuring these bubbles are eliminated, thus preventing decompression sickness.

14. Don’t Touch the Marine Life

Many of the marine animals you’ll encounter on your dives are fragile creatures that can get hurt by a simple touch. There are also species of fish that secrete mucus as a form of protective barrier against external environments. By touching them, you alter that protection and the fish become vulnerable to contamination.

By keeping your hands to yourself you are also protecting yourself. Corals can be sharp and cause lesions and some animals will bite if you get too close. You may also come across poisonous aquatic creatures that won’t hesitate to use their venom if they feel threatened. Some are extremely dangerous for humans.

15. Clear Your Ears

The most common injury experienced by divers is some form of barotrauma to the ear, meaning injury caused by pressure. It generally occurs when the pressure in the middle ear doesn’t equal to the pressure of the outside environment during descent. The first 4.2 meters (14 feet) are especially riskier because of the rapid change in relative gas volume as the diver descends during the first part of the dive.

You can clear your ears by pinching your nose and blowing gently, a method called the Valsalva Maneuver. Another way to equalize is to use your throat muscles to open the Eustachian tubes to allow higher-pressure air from the throat to enter your middle ears. This is done by swallowing; with every gulp, you’ll hear a “pop” that tells you they’re open.

16. Check Your Gauges Regularly

Checking the pressure gauges is also among the essential scuba diving safety tips you need to know about. It may sound obvious yet it’s easy to forget. You can only remain underwater for as long as you have air in your tank. If you check your pressure gauge and surface with a reasonable reserve of air (at least 50 Bar or 500 PSI) in your tank, it’s unlikely you’ll run out of air.

A good rule of thumb is to designate a third of your air supply for the outward journey, a third for the return journey, and keep the final third as a safety reserve. This is called the rule of thirds.

17. Perfect Your Buoyancy

Maintaining optimal buoyancy is a key scuba diving safety rule. Having proper buoyancy means you’ll ascend and descend at will with little effort. But if you have poor buoyancy skills, you’ll struggle throughout the dive and may even make serious errors that negatively affect gas consumption or cause uncontrolled ascents, among others.

18. Don’t Panic

Panic is among the main causes of diver fatalities. In the grip of a panic attack, it’s hard to think rationally and you can become a danger to yourself and also your diving buddies. Learn to recognize the signs of panic in both yourself and others and practice meditation and breathing techniques. If you ever feel too anxious to continue the dive, signal your buddy and have them help you make a safe ascent.

Before a dive, it’s advisable to practice visualization. Go over the things that might go wrong and learn how to solve them. Being informed and prepared should decrease the risk of panic and help you keep a clear head should problems arise.

19. Bring a Dive Computer

Using a dive computer is one of those essential scuba diving safety measures taken by almost all divers today. It’s also a must if you perform multiple dives within a day. This piece of equipment makes your life easier by performing all the complicated calculations in relation to the time and depth of a dive automatically. Because they’re able to continually re-calculate based on changing data, divers can remain underwater for longer periods of time within reasonably safe limits.

20. Be Aware of Boats

Most recreational dives are boat dives, and even if you don’t come by boat, you’ll still share the waters with other vessels. Boats may not observe your presence, so don’t assume they can see you ascending. This may sound like a pretty obvious scuba diving safety tip, but you should always remain aware of what’s above you, as accidents do happen.

One of the most commonly used tools to signal your presence in the area are surface markers buoys and delayed surface marker buoys (or safety sausage). Another item you can use is the dive flag, which is actually required in some diving locations.

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Scuba Diving Safety After Your Dive

21. Don’t Fly Immediately After a Dive

Most organizations agree that it’s important not to board a plane the next 24 hours from your dive. This is especially true for dives requiring decompression stops, while for no-decompression dives you can reduce the time to 18 or even 12 hours, according to Divers Alert Network.

The reason for avoiding flying right after a dive is to avoid increasing your risk of developing decompression sickness. Flying increases this risk because of the decreasing atmospheric pressure during ascent. After your dive, you may still have some microbubbles in your system which could expand during flight.

22. Don’t Zipline

While not exactly as dangerous as flying, going ziplining less than 24 hours after your dive may trigger decompression sickness. If you’re ziplining at a sufficiently high altitude, you may experience the symptoms of DCS. Elevation before a dive, however, should not be an issue, so you can still schedule it during your trip.

23. Don’t Go Mountain Climbing

Mountain climbing is another activity you should avoid after a dive, and this is also due to the change in altitude that can cause DCS. As with ziplining, if you want to include this activity during your trip, best do it before the dive to avoid potential health problems.

24. Don’t Drink (Too Much)

We hate to curb your enthusiasm right after a dive, but one of the general scuba diving safety rules involves alcohol. While you may rightfully want to celebrate your dive with your buddies, you may want to postpone it a bit. Drinking alcohol right after a dive is another factor that may affect your body’s ability to eliminate nitrogen.

Furthermore, dehydration is one of the causes of DCS and as we all know, alcohol contributes to dehydration. Being intoxicated can also mask the symptoms of DCS, preventing you to seek medical attention when needed. Best wait a few hours before drinking any amount of alcohol.

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Do you have any other essential scuba diving safety tips worth sharing? Leave us a comment below and tell us how you keep yourself safe during your diving trips.

There are dozens of specialty diving certifications you can obtain depending on your level of experience and expectations. Whether you’re looking to move on to more advanced types of diving or you’re just curious to see what other options there are, we’ve got you covered. 

Diving can be divided into two large categories: scuba diving and freediving. While freediving is done at breath-hold, scuba diving requires a breathing apparatus. There are many different types of scuba diving, each defined as either recreational or professional. Let’s go over each of the common types of diving and their main characteristics.

Scuba Diving

Recreational Diving

Training: Recreational diver training is done by instructors who are themselves certified to conduct diving courses for specific levels of expertise. Some of the most known and recognized training agencies are PADI, SSI, NAUI, CMAS, and TDISDI. Certifications issued by internationally-renowned organizations will be recognized by diving operators anywhere in the world.

Drift Diving

Drifting is one of the most rewarding types of diving, but one that requires knowledge and precaution. As opposed to other forms of diving, drift diving implies going where the current takes you rather than planning where you go. The force that moves divers may be an ocean current, tidal current, or the natural course of a river, depending on where you’re diving.

Drift diving is relaxing and it’s also the quickest way to get to your next point of interest. However, the current may carry you to unpredictable places. As such, this form of diving requires a good sense of navigation, scuba diving experience and confidence. As you learn to go with the flow, it will almost be like you’re flying, as many divers describe the feeling of drifting.

While drift diving is generally safe as long as divers are properly trained and carry the right equipment, there are a few things to consider. Divers need a surface marker buoy (SMB) or a delayed surface marker buoy (DSMB) so that the skipper of the dive boat knows where they are. Being separated from other divers and taken away from the dive site to unknown waters are dangers to be aware of. 

Popular Drift Diving Sites 

• Blue Corner, Palau – A 30-meter (98 feet) dive with abundant marine life and strong currents that often require a reef hook.
• Washing Machine, Bahamas – The currents can roll divers head over heels, sweeping one down to 12 meters (40 feet) then lifting them back up at 5 meters (15 feet).
• Batu Bolong, Komodo – A macro lovers’ haven, filled with marine fauna of all sizes and well-preserved coral gardens. Some parts of the site may become inaccessible because of the strong current.
• Tumakohua Pass, Fakarava – Divers enter through a canyon from where the current takes over and transports them through the channel. Lively dive where one may spot schools of sharks numbering over 100 members.

Wreck Diving

There’s something terribly intriguing in exploring mysterious wrecks underwater. Some have been on the bottom of the ocean, sea or river for thousands of years.  Many are among the last physical remnants of tragedies that happened throughout the course of history. Most of these wrecks are taken over by underwater flora and attract ecosystems of fish that bring life to these artificial constructions.

While not all wrecks offer something to be discovered, there are plenty of pirate ships and large vessels where one can still observe their mechanical parts and different items they were carrying before sinking. But not all wrecks are ships or boats. Airplanes, submarines, trains, buses, and naval radar stations are also among the popular types of wrecks divers can explore.

Wreck diving is generally safe, but it does come with a few risks. Venturing inside a wreck may result in an injury or getting stuck in parts of the wreck. These are unstable structures that break apart continuously. Divers also face the danger of getting tangled in rigging, fishing nets, or even their wreck reel. Even if one doesn’t go inside, there’s still the risk of suffering lacerations when swimming too close to it. 

Popular Wreck Diving Sites 

• SS President Coolidge, Vanuatu – One big, luxurious wreck! Nearly 200 meters (650 feet) long and 25 meters (16 feet) wide, resting at a depth of 70 meters (230 feet). Guns, cannons, trucks, helmets, and other items can be seen.
• USAT Liberty, Bali – The signature dive in the area. An accessible wreck dive smothered in marine growth. Divers can encounter spectacular marine species like mantis shrimps and sea anemones, among larger animals.
• Fujikawa Maru, Truk Lagoon – Pink and white soft corals adorn this beautiful ship where shoes, gas masks, beer bottles, and other items can be found. One of the best sites for wreck penetration. 
• C-53, Cozumel – Also known as Felipe Xicotencatl, the minesweeper is popular for being an accessible wreck with large openings that allow for penetration. It’s a rather clean wreck, most likely because of the currents that circulate the area.

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Deep Diving

What is considered a deep dive depends on the scuba diver training organization, but a deep diving certificate generally allows one to dive down to 40 meters (131 feet). Most divers want to obtain this certification so that they can dive wrecks, caverns, and caves. Or one may simply want to swim alongside marine creatures that inhabit deeper waters and see coral plateaus sitting at depths of around 40 meters.

Some risks are associated with this type of scuba diving, however. Decompression sickness is the main risk, and it occurs because the deeper you go, the quicker the nitrogen is dissolved into the tissues of the body. Decompression stops need to be carried out during ascent to allow the body to expel the inert gases from the body.

Popular Deep Diving Sites 

• The Great Blue Hole, Belize – A UNESCO World Heritage Site, it’s the largest natural formation of its kind, measuring about 318 meters (1040 feet) across. It has a depth of 125 meters (410 feet).
• Elphinstone Reef, Marsa Alam – This long reef measures over 400 meters (1312 feet) in length and has a maximum depth of about 70 meters (230 feet).
• Tiputa Pass, Rangiroa – Rangiroa is one of the largest atolls in the world, and Tipua Pass is one of the top sites in the area, abounding in marine life. It has a maximum depth of about 46 meters (150 feet).
• Darwin’s Arch, Galapagos Islands – Among the most popular dives in the world, this is the place to go if you want to swim alongside large marine animals.

Cave and Cavern Diving

Cavern Diving

Cavern diving is done close to the entrance of a cave, where one is still able to see the natural light and can easily find the exit. Divers swimming these waters don’t usually go further than 40 meters (130 feet) from the surface and always keep the entrance of the cave in sight. Cavern diving is considered a form of recreational diving that requires a specialty diver certification from any open-water training agency.

Although less dangerous than cave diving, cavern diving is not without risk. Common things that may occur during a dive involve the misuse of a guideline to open water, not adhering to the rule of thirds, giving in to the lure of the deep and venturing too far without proper skills and equipment. 

Cave Diving

Cave diving is a form of technical diving that requires several years of training, special certification, and a different set of equipment than that used for open-water and cavern diving. It’s done as an extreme sport, for research purposes, or for the recovery of lost divers.

As with penetration diving, in case of an emergency, the diver cannot swim vertically towards the surface; they must swim the entire way back out. Navigating complex cave systems can be difficult, with exit routes at considerable distances. Many consider cave diving one of the deadliest sports in the world, yet this is mostly because of poorly trained divers that venture into caves without the proper set of skills and equipment.

Being among the most dangerous types of scuba diving, there are several dangers associated with cave diving. These include encountering an overhead environment that prevents one from making an unplanned exit to the surface in case of emergency, increased air consumption due to stress, sediment that causes visibility to drop to near zero, and so many other risks.

Popular Cave and Cavern Diving Sites

• Orda Cave, Perm – The largest underwater gypsum cave in the world, with a length of 4,600 meters (15,092 feet). Incredibly clear water due to the gypsum rock that acts as a filter.
• Kilsby’s Sinkhole, Mount Gambier – A 65-meter (213-foot) limestone cavity filled with fresh water. Used for recreational diving and as a training site for police divers.
• The Pit Cenote, Tulum – The deepest cenote in Quintana Roo, measuring 119 meters (391 feet) in depth.
• Cenote Dream Gate, Tulum – Many say it’s the best cavern dive in the area. Requires excellent diving skills so as not to destroy the fragile rock formations.

Night Diving

Night diving is diving in little to no ambient light. It often occurs at night, but it may also occur at dusk. Furthermore, cave diving, diving in murky or extremely low visibility water, and diving under an overhang may also be referred to as night dives. Divers need to complete a specialty course to be allowed to go on night diving trips.

But why would one go on a night dive? Firstly, because it’s a totally different experience. There are many nocturnal animals that shy away from daylight and you may only observe them during the night. There are also bioluminescent creatures that emit their own light, and it’s pretty magical to see them. Night diving also ensures some amazing shots for underwater photographers. 

Darkness creates some risks divers need to be aware of. Flashlight failure is the most obvious one; it leads to loss of visual references, inability to control depth or to read instruments and control buoyancy. Precautions such as bringing three lights – a powerful main light of about 1,100 lumens, a backup light, and a signal light – are in order. Bear in mind that shining light into other divers’ eyes can damage their night vision.

Popular Night Diving Sites

• Pearl Rock, Fiji – Perfect location for night diving for those interested in diving with sharks.
• Blue Lagoon, Bali – White-tip reef sharks, strange crabs, lobsters, and the Spanish dancers are among the creatures one can expect to see here during the night.
• USS Kittiwake, Grand Cayman – Lively marine life out hunting during the night by the moon-lit wreck.
• San Francisco Wall, Cozumel – A healthy, shallow reef featuring low current where an abundance of aquatic creatures come out of hiding at night.

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Technical Diving

There’s some disagreement as to what technical diving is. However, there’s a general agreement that technical diving is a type of scuba diving that exceeds the limits of recreational and commercial diving for depth and bottom time, involves accelerated decompression, and makes use of variable gas mixtures. 

Tech diving also means exposure to a (natural or artificial) ceiling that does not allow the diver to ascent to the surface vertically. Consequently, cave and wreck diving are considered by some to be forms of technical diving. A technical diver is also prevented from making a quick ascend to the surface due to decompression obligation.

Technical diving may expose the diver to dangers beyond those normally associated with recreational or commercial diving. Going deep for longer periods of time poses more risks for techs than other types of scuba diving. Some of the main ones involve decompression sickness, improper breathing technique, overexertion, and misuse of diving equipment.

Popular Technical Diving Sites

• San Francisco Maru, Micronesia – Sitting at a depth of 64 meters (210 feet), the shipwreck holds are filled with tanks, torpedoes, and mines.
• Drop Off, Verde Island – A haven for recreational and technical divers alike. The reefs and drop off goes all the way down to 75 meters (250 feet).
• Tower, Sharm El Sheikh – Spectacular dive site that features a 120 meter- (394 foot-) long canyon.
• Anemone City, Sharm El Sheikh – Features a beautiful big reef with walls descending to a depth of about 150 meters (492 feet).

Ice Diving

One of the most challenging types of scuba diving, ice diving is a penetration dive that takes place under ice. The dive time is limited to less than 30 minutes to reduce exposure to freezing temperatures. Ice divers usually dive one at a time while the other team members ensure the diver’s safety.

But why would anyone want to dive under ice? For starters, ice diving can provide unique encounters with animals such as penguins and seals or animals you may not be able to observe during summertime. Furthermore, those diving in freshwater will notice that clarity tends to increase in the winter due to lack of water circulation.

There are many risks associated with ice diving; hypothermia, getting lost under the ice, and regulator failure are among the main ones. Divers are always tethered for safety, meaning they must wear a harness clipped to a safety line that is secured above the surface.

Popular Ice Diving Sites

• Lake Baikal, Russia – The world’s oldest lake, home to an enormous number of endemic species.
• Rummu Quarry, Estonia – A former limestone mining site and prison turned into an adventure center where one can practice different outdoor sports.
• Sea Of Okhotsk, Shiretoko Peninsula – This dive site offers divers a chance to swim with sea angles (clione) and admire anemones and sea urchins.
• White Sea, Russia – Great visibility, amazing photographic opportunities, and abundant fauna. A good place to spot Beluga whales.

Altitude Diving

Altitude diving is defined as the type of diving that takes place in waters found at altitudes higher than 300 meters (1,000 feet) above sea level. While most divers only experience dives below sea level, there are plenty of high-altitude dive sites around the Globe that offer a select few unique underwater experiences. 

High altitude poses some unique challenges divers may otherwise not experience when diving at sea level. Reduced atmospheric pressure and freshwater affect the depth gauges. Altitude divers are also more exposed to decompression sickness because the effect of diving at altitude is greater than it would be at sea level. Because of this, there are shorter no-decompression times.

Popular Altitude Diving Sites

• Lake Titicaca, Peru – Situated at 3,810 meters (12,500 feet), it is the highest elevation lake where recreational diving is allowed. The majority of the fish found here are endemic species.
• Yellowstone Lake, Wyoming, U.S.A. – With an elevation of 2,372 meters (7,783 feet) and fast-paced currents, it’s the perfect high-altitude adventure dive.
• Lake Atitlán, Guatemala – Located at 1,562 meters (5,026 feet), it’s a massive volcanic crater where divers can see volcanic hotspots and rock formations.
• Weissensee, Austria – Also an ice diving spot, the lake is famous for its crystal-clear waters and resident fish which grow to large sizes.

   Professional Diving

Training: Professional divers are trained to dive safely as a member of a dive team and to gain the specific skills required for their employment. Training is usually done through registered diving schools and varies according to the legislative requirements of each country. Military diver training is usually done in the same armed force where the diver will be operating in, and it’s provided by a specialist training establishment.

Commercial Diving

Commercial diving covers a wide array of activities and tasks, and it’s not always limited to the offshore environment. These highly skilled professionals work in dangerous circumstances with difficult work schedules. Lots of training is required to succeed and stay safe in these careers.

Most often, this type of scuba diving is associated with the oil and gas industry.  However, commercial divers also work on land-based civil engineering operations, in hazardous materials environments and nuclear power plants. Scientific divers and media divers (filmographers and photographers) are also among the common types of commercial divers.

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Rescue Diving

Rescue diving is a challenging and rewarding profession. These divers respond to emergency situations, most often when there are other divers underwater in need of help. These experienced professionals are trained in depth rescue, surface rescue, first aid techniques, and emergency management, among others.

Yet you don’t have to be a professional to earn a rescue diver certification. Anyone who wishes to learn how to manage problems in the water and become a better diving buddy can enroll in a specialized course at any of the diver training agencies offering this option. 

Military Diving

Military divers work in various branches of the armed forces, including marines, army, air force, the navy, and coast guard. They’re essential to many missions, doing combat work, search and rescue, ship maintenance operations, underwater engineering, and bomb disposal, among others.

Freediving

Training: Freediving is not for everyone, but those that wish to pursue it either recreationally or competitively can take freediving/apnea courses provided by AIDA, Apnea Academy, PADI, NAUI, SSI, CMAS, FII, PFA, TDISDI, and other recognized diving organizations and agencies.

Humans first started freediving out of necessity, mostly for food and items which they could then sell, but also to recover items lost overboard. As time passed, it has evolved into a pastime activity and even a popular sport. 

Freediving – or apnea diving – is diving while holding one’s breath, without the help of a breathing apparatus. Various techniques help freedivers stay underwater longer and go deeper with only one breath of air. Some define freediving as an advanced form of snorkeling, but it’s so much more than this.

But why would one freedive and expose themselves to risks that are minimized when using a breathing apparatus? Freediving offers an exhilarating experience; there’s no heavy equipment holding you down, you can twist and turn with ease, come closer to marine animals, and allows you to get to know yourself better both mentally and physically. 

Freediving requires a lot of discipline and great swimming skills. It’s a dangerous activity that can result in fatalities. Drowning is a huge risk, and so is shallow-water blackout, which is the loss of consciousness due to lack of oxygen to the brain.
Competitive freediving, however, is a rather safe sport because all competitions are held under AIDA authority where strict safety rules are imposed.

Popular Freediving Sites

• MS Zenobia, Cyprus – The wreck of a massive ship that French freediver Guillaume Néry described as being so big it resembles an underwater building.
• Dean’s Blue Hole, Bahamas – Famous “playground” for professional freedivers. It’s the world deepest blue hole, bottoming out at 202 meters (662 feet).
• Christ of the Abyss, Italy – A submerged bronze statue honoring Dario Gonzatti, the first Italian to use scuba gear, who lost his life to scuba diving in 1947.
• Blue Hole, Sinai – This 56-meter (184 feet) dive site is reputed for having the largest number of fatalities in the world. A popular freediving training site, as the reef surrounding it protects it from currents and waves.

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Which of these popular types of diving have you tried so far and what are you ready to experiment with next? Leave a comment below and tell us about your diving experiences!

About 71 percent of the Earth’s surface is covered with water, most of it found in oceans. There are thousands and thousands of spectacular diving locations throughout the Globe. It would take a few lifetimes to explore them all, so we’re always looking for ways to discover those that are most worthy of our attention.

Picking the best scuba diving in the world was no easy task but at the end of the day, after debating over the most memorable of all experiences, we’ve settled on these ten spots. From some of the most diverse ecosystems in the world to eerie underwater caverns, here are our favorite diving locations for blowing bubbles.

Darwin’s Arch, Galapagos Islands

Depth	30m/98ft – over 40m/131ft	Dive Type	Drift, Reef
Visibility	10m/32ft – 20m/65ft	Diving Period	All year round
Current	Medium to Strong	Experience	Advanced
Water Temperature	20 – 28° C/68 – 82° F	Access	Liveaboard
Marine Life	Whale sharks, hammerhead sharks, Galapagos sharks, tiger sharks, moray eels, eagle rays, sea lions, turtles, ocean sunfish, bottlenose dolphins

Located off Darwin Island, the northernmost island in the Galapagos archipelago, Darwin’s Arch is a haven for those who want to swim alongside large aquatic animals. It comes as no surprise that this area is considered one of the greatest marine wonders of the world.

The epicenter of the site is the arch, a natural rock that sits above the surface of a flat plateau. Strong currents wrap around the dive site and from June through November the presence of the Humboldt Current is felt the strongest. During this period divers get to experience sightings of whale sharks along with the regular schools of marine animals.

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Cape Kri, Raja Ampat, Indonesia

Depth	3m/10ft – 40m/131ft	Dive Type	Drop-off, Drift, Reef
Visibility	10m/32ft – 30m/98ft	Diving Period	All year round
Current	Medium to Strong	Experience	Advanced
Water Temperature	27 – 30° C/80 – 86° F	Access	Boat, Liveaboard
Marine Life	Dogtooth tuna, giant trevallies, jacks, chevron barracudas, snappers, white-tip reef sharks, Wobbegong sharks, dolphins, giant groupers

Located off the island of Kri in the province of West Papua, this is one of the most remote dives in Indonesia. The crossroads of currents at the tip of the Island of Kri has turned Cape Kri into a dive site of incredible variety of underwater flora and fauna. The pristine waters are home to untouched reefs and unique marine life, with new species continuously being discovered.

The reef is a sloping wall passed by schools of fish daily and at the base of the reef, at a depth of 38 meters (124 feet), lies a snagged anchor. Among the attractions it’s also worth mentioning a spot called The Passage that experiences very strong currents and it’s suitable for divers with at least 50 logged dives.

Note that Raja Ampat is a designated marine biodiversity park and divers must purchase a permit to visit the area. This helps fund the conservation efforts in the area. The permit is valid for one year.

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Barracuda Point, Sipadan Island, Malaysia

Depth	5m/16ft – 40m/131ft	Dive Type	Wall, Drift, Reef
Visibility	30m/98ft	Diving Period	All year round; best April – December
Current	Medium	Experience	Intermediate to Advanced
Water Temperature	27 – 29° C/80 – 84° F	Access	Boat
Marine Life	Barracudas, Napoleon wrasse, bumphead parrotfish, reef sharks, hammerhead sharks, jacks, turtles

Also known as Punt’i Piku, Barracuda Point is located off the coast of Sabah, Malaysia. Teeming with life, it is without a doubt one of the best dive sites in the world, home to over 3,000 species of fish and an abundance of corals. Dozens of fish patrol the area, and divers may find themselves in the middle of a swirling vortex of barracudas and jacks.

The dive follows a vertical wall rich with gorgonians, black corals and soft corals of all shapes and colors. The wall levels out into a sloping plateau covered in Elandshor corallus and Hersthoorn corals that offer excellent opportunities for underwater photographers.

Note that visitors require a permit for diving and snorkeling at Sipadan Island. The number of permits is limited to 120 a day, divided across 12 tour operators.

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Dirty Rock, Cocos Island, Costa Rica

Depth	10m/33ft – 35m/115ft	Dive Type	Reef
Visibility	More than 30m/98ft	Diving Period	All year round
Current	Strong	Experience	Advanced
Water Temperature	22 – 24° C/73 – 75° F	Access	Boat
Marine Life	Hammerhead, Galapagos, silver-tip, white-tip, silky, whale, and tiger sharks; eagle rays, lobsters, green turtles

Dirty Rock is one of Cocos Island’s most impressive rock formation. It’s a sheltered channel featuring rock pinnacles and volcanic boulders rising above the waves. And in case you were wondering where Dirty Rock gets if unfortunate name, its appearance is the result of sea birds bombarding the rocks with guano. 

This site is considered one of the top dive sites in the world due to the large number of hammerhead sharks and impressive biomass of fish that inhabit these waters. Towards the island’s pinnacle there’s also small cave full of marine animals like lobsters, turtles, eagle rays, and octopus.

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Blue Corner, Palau, Indonesia

Depth	8m/26ft – 30m/98ft	Dive Type	Drift, Reef, Drop-off
Visibility	15 – 40m/59 – 104ft	Diving Period	All year round; best November – May
Current	Medium to Strong	Experience	Advanced
Water Temperature	28 – 30° C/84 – 86° F	Access	Liveaboard
Marine Life	Reef, bull, tiger, white-tip, leopard, and whale sharks; barracudas, trevallies, nudibranchs, snappers, dog-toothed tuna, hawksbill and sea turtles, parrotfish, mackerels

Located northwest of Ngemelis Island, Blue Corner is a world-famous dive site that offers an adrenaline-fueled experience. With currents that can get extremely strong and that change direction at any moment, it’s not a dive for anyone. In fact, the story goes that the reef hook was invented in Palau.

This underwater promontory of 15-20 meters is a true wonderland that provides the perfect vantage point for the witnessing marine life on the reef. As one drifts across thousands of species of coral, a miriad of aquatic animals can be observed. The reef abounds in hundreds of species of reef fish, from the tiny nudibranchs to large creatures like sharks and whales.

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Monad Shoal, Malapascua, The Philippines

Depth	30m/98ft – over 40m/131ft	Dive Type	Drift, Reef
Visibility	10m/32ft – 20m/65ft	Diving Period	All year round
Current	Medium to Strong	Experience	Advanced
Water Temperature	20 – 28° C/68 – 82° F	Access	Liveaboard
Marine Life	Thresher sharks, mobula rays, manta rays, devil rays, octopus, skeleton shrimps, nudibranchs, cardinalfish, damselfish, gobies, cowries

Monad Shoal, or Thresher Shark/Shark Point, is one of the best dive sites in the world – if not the ultimate one – to see the timid thresher sharks. Located off Malapascua Island in the Philippines, Monad Shoal is actually an underwater island rising from a depth of 200 meters (656 feet) and terminates at 15 meters (50 feet) below the surface. 

Thresher sharks are shy creatures, but they come here early in the morning to the cleaning station. And while there are no guarantees of seeing the sharks on a first dive, diving at Monad a few days in a row increases the chances of encountering them several times. 

The thresher sharks are not the only attraction at Monad Shoal. After dropping over the edge of the plateau, divers can spend hours observing the biodiverse reef wall made up of a multitude of species of soft coral, some so large that one can easily hide behind them. The wall also features crevices that shield small fauna like shrimps and nudibranchs.

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The Aquarium, Socorro Island, Mexico

Depth	10 – 30m/33 – 100ft	Dive Type	Drift
Visibility	24 – 30m/80 – 100ft	Diving Period	November – May
Current	Medium to Strong	Experience	Advanced
Water Temperature	21 – 28° C/70 – 82° F	Access	Liveaboard
Marine Life	Galapagos, hammerhead, silky, white-tip, silver-tip, tiger and whale sharks; whales, manta rays, dolphins, wrasses, tuna, barracudas, jacks, marlins

The Aquarium is the macro dive site off Socorro Island, Mexico. This spot is one of the unmissable dives of the island; from offshore, divers can admire and get close to whales. Socorro Island is actually one of the few places in the world where one can dive with humpback whales. 

Visiting The Aquarium does not come without challenges. The location is accessible only through liveaboards that usually run during the high season of November to May. During this period, the large aquatic creatures that inhabit these waters are plentiful.

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USAT Liberty, Bali, Indonesia

Depth	5 – 30m/16 – 100ft	Dive Type	Wreck, Reef, Muck
Visibility	10 – 35m/32 – 115ft	Diving Period	All year round
Current	None	Experience	All levels
Water Temperature	23 – 30° C/73 – 86° F	Access	Shore
Marine Life	Ghost pipefish, nudibranchs, garden eels, batfish, anglerfish, sweetlips, yellow mask surgeons, butterfly fish, fusiliers, white-tip sharks, barracudas, Napoleon wrasse, trevallies, pygmy seahorses, parrotfish, lizardfish, jacks, gobies

The USAT Liberty was a cargo ship that sank off Bali’s northeast coast in 1942, after being torpedoed by a Japanese submarine. Today, the ship is regarded as one of the best wreck dive sites in the world, beaming with marine life – from colorful reef fish to sea turtles.

The ship was taken over by a variety of species of soft and hard corals, gorgonians, sea fans and other underwater flora.  And while the 120-meter-long structure is disintegrating, it is still possible to swim into some of the large cargo holds. Divers can still observe the bow, guns, and anchor chain of the wreck.

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The Pit, Cenotes, Mexico

Depth	119m/391ft; 40m/131ft for guided dives	Dive Type	Cavern
Visibility	Over 100m/328ft	Diving Period	All year round
Current	None	Experience	Advanced
Water Temperature	Around 26° C /79° F year-round	Access	Shore
Marine Life	Unknown

The Pit is a spectacular dive site located in the jungle between Tulum and Playa del Carmen. This incredible sinkhole is one of the deepest cenotes in Quintana Roo. At the surface, an oval-shaped opening leads way to a cylindrical cavern with an overhang of stalactites, opening to another cavern rimmed with large stalactite and stalagmite formations.

Sun rays penetrate to the depths where they meet a cloud of hydrogen sulfate, creating an eerie atmosphere. As one dives further into the depths, they go into a thick white fog that creates a feeling of weightlessness. The Pit truly is one of the most surreal and spectacular dives in the world.

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SS Thistlegorm, Sharm El Sheikh, Egypt

Depth	16 – 33m/52 – 108ft	Dive Type	Wreck
Visibility	15 – 25m/49 – 82ft	Diving Period	All year round
Current	Strong	Experience	Intermediate to Advanced
Water Temperature	22 – 28° C/71 – 82° F	Access	Boat, Liveaboard
Marine Life	Goupers, angelfish, barracudas, lionfish, sweepers, stonefish, scorpionfish, Mediterranean moray eel, tuna, snappers, turtles

Found off the west coast of the Sinai Peninsula, the SS Thistlegorm is one of the best-preserved wrecks in the world. Now measuring 150 meters in length, the ship lies upright on the sandy seabed where divers can expect to see much of the cargo, motorcycles, cars, locomotives, anti-aircraft guns, and other remains from its past.

Due to its long time underwater, the upper deck is now encrusted with beautiful coral formations. The hull is where lionfish and schools of sweetlips take shelter from the current, and as one makes their way up across the top of the SS Thistlegorm, the waters become abundant in different species of fish that roam the area unperturbed by the familiar divers.

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Has your favorite diving site made it on our list?
Where have you experienced the best scuba diving in the world?
Share your thoughts in the comments below!