The remains of dead animals, tossed into the bottom of a cave away from the light of day who-knows-how-long ago, have resurfaced in a most unexpected way.

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Deep in the jungle outside Tulum, Mexico, divers, conservationists, and tourism leaders have combined forces to provide public access to this totally unique section of the world’s second-longest underwater cave system. Under continual exploration since its 1987 discovery, the Dos Ojos underwater cave system extends for an estimated 51 miles, filled with crystalline, balmy freshwater accessible via 28 known sinkholes – locally called “cenotes” (say-NOH-tays). 

Throughout the course of these explorations, a team of divers came upon a truly marvelous discovery. Its jaw-dropping rock formations were punctuated by stalactites and stalagmites, with pockets of darkness in which cave blind fish flourish. Most staggering of all, the bottom of the pool had a soft, dune-like surface which, when shifted, revealed unforeseen treasures: the pit was littered with animal bones ranging from ancient to more familiar, including the lower jawbone of a tapir and the fossilized remains of an extinct prehistoric camel.

Visitors to the site, now called Pet Cemetery after these finds, can still see these skeletons and more, in their original positions. Scientists have pieced together a theory that the sinkhole was used as a disposal pit long ago, before the water table rose and flooded the animals’ mass grave. The location itself is not the most suited for beginning SCUBA divers, with shallow depths and fragile rock formations on all sides; snorkeling, however, is an option at the site. With respect for the fragility and unique nature of the Pet Cemetery Cenote, it is requested that interested divers choose their participation method according to their skill level, so as to best preserve the wonder for generations to come. 

Above ground, in the jungle trek en route to the cenote, living ancestors of these animals are on full parade. Spider monkeys are a common sight in the trees above, not to mention more common ground-dwelling creatures of rainforest climes, all of whom prove equally awe-inspiring to divers above water as their deceased brethren at rest below the waterline.