Amazing Underwater River in Mexico

This unbelievable site is located in a water-filled cave – or cenote (pronounced say-no-tay) – in Mexico’s Yucatan Peninsula. What appears to be an underwater river flows placidly through the cave, offering up one of the most stunning sights ever captured in underwater photography.
The “river” is actually a thin layer of hydrogen sulfate separating the fresh water at the top from the salt water below. Divers can swim right through the “river” to view it from below. Underwater trees line the river, contributing to its bizarre and otherworldly appearance.