Scuba Diving the Caverns of Mexico: What is a Cenote?

Cavern Diving in Mexico: What is a Cenote and Why Would I Want to Go Scuba Diving in One?

“Cenote” is a word unique to Mexico derived from the Mayan word ts’onot, meaning “well,” and was used to describe any place where sinkholes formed when the earth collapsed over limestone hollows and caves providing access to the underground freshwater sources below.

These pits figured prominently in Mayan culture, as places of worship, sources of life and places of sacrificial death.

Fresh water, having spent perhaps millions of years seeping and dripping through the limestone bedrock formed unimaginable numbers of delicate stalactites, stalagmites and columns, producing labyrinths and formations that are complex, menacing at times but always stunning to behold! These dry caves were eventually flooded, thus effectively bringing to a halt to any additional formation.

A quick mental note:

  • Stalactites are mineral structures formed from the ceiling downward – “stalactites hold tight.
  • Stalagmites are formed from the ground up – “stalagmites grow with might.”
  • Columns are formed when stalactites and stalagmites grow to reach each other and form a single structure.

Interestingly enough one very desirable quality of caverns is the presence of a halocline, where dense saltwater flows underneath the lighter freshwater. Where the two meet creates an unusual visual disturbance very much like a thermocline, but more pronounced altogether. In very deep pits it is not uncommon to find an even denser layer of a hydrogen sulfide and saltwater mixture that creates the appearance of a cloud or the kind of very low fog you might see settle across the graveyard in a spooky movie! That layer tends to limit visibility to just a meter or a few feet. I’m not sure how, but you can actually get a sense of the smell of the hydrogen sulfide underwater, as well; it’s similar to rotten eggs but not nearly quite as intense.

Open Water Scuba Divers: Cave and Cavern diving experience or certification is NOT required to dive in the cenote caverns!

Diving the caves and caverns of the cenotes scattered across the Yucatan Peninsula is truly a unique experience, but not one that should be taken lightly or without guidance. Make no mistake about it, even diving in the caverns, where a diver should always be within sight of the cenote’s natural light zone, is not without risk.
Scuba Diving the Cenote Caverns and Caves in Mexico

Keep in mind that while in cenotes, regardless of whether you are in a cavern or cave zone, you are diving in an overhead environment, which involves an additional level of risk. While cavern diving in Mexico does not require you to have a Cavern Diver specialty certification, we HIGHLY recommend it! You will, however, require a properly trained and certified cavern guide to go diving in all cenotes accessible to the public. Mexican safety standards require that the cavern guide be “Full Cave” certified, possess fully redundant equipment and may guide no more than 3 other divers at a time.

The cenote cavern diving experience:

Perhaps L Scott Harrell, a very experienced dive traveler and veteran scuba instructor, said it best about diving the cenotes caverns:

I’ve been diving in many places around the world since 1988 and am a scuba instructor as well. Recently, I was looking for something VERY special to give myself on the occasion of my 40th birthday when I decided on a “gift of diving.” Diving the cenote caverns between Playa del Carmen and Tulum, Mexico has always been a dream of mine, and since I live so close here in Cozumel, I thought it was time to cross that off of my own diving “bucket list.”

Well… I’m just now recovering from three solid days of diving the dark and beautiful world of the underwater caverns between Playa del Carmen and Tulum, Mexico. It was an experience unlike I have ever had in my 24 years of scuba diving.

I dove in cenotes (pronounced say-note-ays) called Chikin-Ha, Calaveras (aka: The Temple of Doom), Taj Mahal, Gran Cenote, Dos Ojos (Barbie line and Bat line), The Pit (this was a very deep dive at 151 feet) and Pet Cemetery.

It was a physical, gritty, beautiful, challenging, exhausting and enormous adventure I undertook for my 40th birthday and it was definitely in the top three dive experiences of my life… right behind swimming with whale sharks earlier this year and scuba diving with bull sharks.

I am profoundly at peace as a result.”

The best advice we can give you is to find a professional cenote dive guide who will guide you properly, look after your safety and give you the information you need to really enjoy your diving in the caverns. Keep in mind, as in all instances of scuba diving, you alone are responsible for your safety; underwater and specialty training only makes each of us better and safer divers. We’d be happy to refer you to a highly qualified underwater scuba guide.

Some points to keep in mind:

  • Your safety in the caverns should be your first and foremost concern. Period.
  • Cavern diving requires extra safety gear. Your guide should provide most, if not all, of that to you.
  • This experience is for novice to advanced divers who have very good buoyancy control. You my need to learn some special diving techniques, such as a frog kick, but your guide should cover that and practice during an excellent cavern orientation and, sometimes, a checkout dive.
  • Water in the cenotes is approximately 74 degrees year around. Most divers require a 7mm wetsuit and a hood at a minimum. We can provide them for you, too. Don’t try to get away with wearing less exposure protection, those who do sometimes find themselves cold and unable to complete a full day of diving.
  • You will NOT have to rinse your gear after a dive, it’s freshwater!
  • The cenotes dotting Mexico are in the jungle, which may involve adventure and the unexpected. Driving rough roads, uneven walkways, sightings of rare animals and sometimes mosquitos are almost certain. All are easily managed, but you should be fit for diving and some light exertion.
  • Most dives will not go below approximately 40 feet, unless you dive “the Pit” (Max depth 150 feet). Caverns tend to be very shallow.
  • If this is your first time diving in a cenote, it will be unlike any other diving experience you’ve ever had. You WILL remember it forever!

Cave Diving Warning Sign often seen while scuba diving in cenotes and caverns in MexicoWarning! Warning! Warning!

NEVER go beyond the signs that mark the end of the cavern zone, leave the cavern line or attempt cave diving without proper education, experience and safety equipment… you will probably die doing so.

If you would like to go scuba diving in the cenotes, let us know. We’d be happy to help you find a qualified cavern scuba diving guide and maybe even go diving with you while you’re scuba diving in Cozumel with us!