Early this year, a pair of professional divers uncovered a new landmark beneath Cancun and the Yucatan Peninsula. After years of searching and thousands of dives, Steve Bogaerts and his dive partner, Robbie Schmittner, were able to find a connection between two massive underwater cave systems. Bogaerts and Schmittner performed more than 500 dives of several hours over a course of four years to connect the world’s second-longest (Sistema Sac Actun) and third-longest underwater caves (Sistema Nohoch Nah Chich). Since then, the Sistema Sac Actun (White Cave System) has assumed the title of the world’s largest underwater cave. At over 95 miles in length, Sac Actun also stands as the ninth-largest cave in the world, including all dry cave systems.
As underground waterways of this size are certainly rare, the development of the cave system over thousands of years provides an equally interesting story. Several unique factors play a role in the creation of the area’s sinkholes and eventually the underground rivers. The stretch of the Yucatan Peninsula known as the Riviera Maya rests on a base of porous limestone, a stone that allows rainwater to easily enter the underground cave systems. Meanwhile, the rainforests of the Yucatan Peninsula attract considerable precipitation, all of which drains toward the Caribbean Sea.
After the water seeps through the limestone and moves slowly east, the relatively flat ground near the coastline fosters the creation of sinkholes – known to divers and scientists as cenotes. Underground, the water becomes slightly acidic and dissolves rock as it moves, carving out these remarkable caves. In fact, these unique ecological elements were also responsible for the world’s previous longest underground cave system – the 91-mile Sistema Ox Bel Ha, also located in the Riviera Maya.
The cenotes, caves and rivers have played an important role in the cultural history of the region, as well. The Mayan culture depended on the fresh water found in these systems for centuries, while the underground rivers currently support the tourist industries of Cancun and Cozumel. At the same time, the rivers are important to scientists analyzing the human impact on the environment. In fact, Bogaerts states that the adventurous divers seeking out the connections of underground rivers serve as the “eyes and hands” of geologists, biologists, chemists and other environmental researchers.
Beyond the thrill of the dive, the cave system highlights important ecological issues regarding the area’s drainage patterns. Bogaerts says, “The point is that they’re so interconnected. There are so many cave systems that if there’s a point of pollution in any one particular area it can spread very extensively throughout the entire system.” According to the divers, “awareness is growing, but it must keep pace with the extremely rapid pace of development.”
For the tourist, the discovery of such underground systems has opened the door to some of the most incredible dive opportunities in the world. Thanks to the connection made early this year, divers can visit several popular cenotes while advanced divers can explore the dark depths of this unique system. Entering the system through one of the area’s numerous cenotes, divers will find over 500,000 feet of caves to explore. According to an online message posted by Bogaerts after the discovery, divers now have the opportunity to explore several popular cenotes as part of a single cave. He claims that “it is now possible to traverse from the Pabilany cenote – west of the Calimba cenote on the Coba Road – around the Grand Cenote (Sac Actun), Cenote Esqueleto (Temple of Doom), Cenote Naval, Cenote Abejas, Cenote Nohoch Kin, bypass Manati, press on to Balancanche, Cenote Nohoch Nah Chich, pass by the Dinner Hole Cenote and end up in the Dirty Dog or Pet Cemetery Cenotes.” If you are familiar with diving around Cancun or have begun researching your trip to the area, this new path is sure to excite.
Bogaerts and Schmitter will continue exploring the Riviera Maya’s underwater caves, searching for more connections. Some have speculated that Sistema Sac Actun could be connected to at least two additional cave systems, caves that would add an additional 125 miles in length. There is even a possibility that the Riviera Maya might surpass the world’s largest cave system – a title currently held by the 360-mile Mammoth Cave system in Kentucky.
Time will tell what else lies beneath Cancun and the Riviera Maya. In the meantime, visitors can explore some of the most important – and undeniably unique – caves in the world.