Cenote Kalimba is located northwest of the city of Tulum, in the Yucatan Peninsula, Mexico. It is part of the Sac Actun System, the largest underwater river system of the world. The family that owns the place, built a kind of altar, with interesting images of Mayan gods and a Christian crucifix in the same spot. There are some restrictions on cave passages, with sidemount being the best way to explore this beautiful cave. Our guide, Mr. Hairo Trejo, showed us bones of a Megatherium, a mammal who lived here about 10,000 years ago when this cave was still dry.