At 12,730 meters Rio Secreto (also known as Pool Tunich) is the longest dry cave in Quintana Roo, so commercial cave or not, when we were invited on an ICS outing to it, we were excited. We were also interested in what the management might (or might not) have done to preserve the cave.

After a brief orientation and an eight kilometer drive into the jungle, we were outfitted with wetsuits and booties (Nice caving helmets are available, but most everyone in the group opted to use his/her own.). Once sunglasses and other non-essentials were safely stored in lockers we began to get serious about the tour. Our fingers were gently crossed we would wind up with Tania’s group, heading southeast at a slow place into a reportedly beautiful white section of cave. It has been awhile since time has allowed a photo shoot, and we were hoping to lag behind with camera. But that group was full, so we took the “sporting” northwestern “wet” route…and despite the fact that the camera died shortly into the cave, we had a blast.

Otto, the general manager for Rio Secreto, was our guide on our extended tour. His enthusiasm for the cave was apparent, and being one of the original explorers he had the expected tales-cavers-tell. We saw some incredible formations: rimstone dams, cave pearl fields, helictites (rare in Quintana Roo and the first we had seen), cave rafts, lettuce, and numerous others. Many of these formations were in staggering numbers, making each room seem more wondrous than the last. It is not an exaggeration to say Rio Secreto has to be the most striking dry cave we have seen in the area.

We traveled some 2.5 kilometers, and hit the end of the cave, a large room with a hole in the ceiling known as “Entrada de la Vasija” for the Mayan vase nearby. A rickety ladder led about 12 meters to the surface, perhaps to aid the tayra which adeptly scampered it as soon as we entered the room. Other creatures encountered during the journey were spiders (wolf spider and a tarantula), a snake (Lizard Eater, Dryadophis melanolomus), bats, and mot mot birds. We didn’t exit via ladder, but took a detour through (yet) another stunning section of the cave eventually leading to a manmade exit.

This short concrete section was done by previous owners, and the new caretakers rightly assume more damage would be done by its removal. Fortunately, the rest of the cave is free of this type of “improvement”. There are no concrete paths through the cave (thankfully), but fortunately—from a conservation standpoint—there are dedicated paths (even through the swimming sections). Guides ensure visitors do not wander, and unobtrusive cave diving-style lines delineate the route and provide an extra measure of safety. (It should also be noted that tours are primarily walking/wading/swimming.)

Lighting can be a problem in tourist caves (see last photo). There are few lights in Rio Secreto; the only ones we saw were a few at the beginning of the tour—and these were battery-powered cave-diving (removable) LED lights submerged in shallow pools, not the cheapest option, but certainly the least intrusive. We didn’t see any others throughout our journey; no electric appears to have been installed in the cave.

Otto said water quality studies are done on a monthly basis and that management has implemented a program whereby students tour the cave, a visual demonstration of the importance of conservation. We took our own water samples and compared them with samples we had previously taken on a field trip to the Calica quarry next door—the lower salinity at Rio Secreto suggesting that its water does not come via Calica. The main threats to the cave would appear to be the high development potential (and consequent sky-high market value) of the land above it, the risk of landowners above attempting to construct their own entrances, and general groundwater contamination from the nearby town of Playa del Carmen, all problems that will require changes in the approach to environmental management in Mexico/Quintana Roo.

A couple days we followed up by asking a local high school student if she knew anything about Rio Secreto. We were pleased to learn that she had gone on a field trip to the cave and considered it one of the highlights of her school year.

Cavers may lament the fact that caves in the region have been subject to the tourism boom; however, because management at Rio Secreto is ecology and community-inclined we are not sure there could be better commercial stewards of this incredibly beautiful place. We also think that visiting cavers who want to minimize their impact on the caves here can achieve this by visiting commercial caves such as Rio Secreto and others which have been conscientiously developed, while at the same time seeing some of the best caves Quintana Roo has to offer.