Longest underwater cave ever discovered may reveal secrets of ancient Mayans

The longest underwater cave ever has been discovered in the Mayan heartlands of Mexico.

Scientists exploring an underwater system found a connection between two caverns, which together form a record 216-mile long labyrinth.

They contain human remains and other items believed to have been left by members of the Mayan culture before the caves later became filled with water.

It hopes that the long-lost secrets within the system could shed new light on the lives and beliefs of the people who first settled in the area some 4,000 years ago.

Members of the Great Maya Aquifer Project (GAM) made the breakthrough in their exploration project after they were able to find a passage linking two previously known caves in Tulum, on Mexico's Yucatan Peninsula.

Project leader Robert Schmittner has been looking for a connection between the two for 14 years, gradually adding details of new tunnels and galleries to the system.

"This immense cave represents the most important submerged archaeological site in the world, as it has more than a hundred archaeological contexts," said Guillermode Anda, a subaquatic archaeologist.

"Along this system,we had documented evidence of the first settlers of America, as well as extinct fauna and, of course, the Mayan culture."

Many caves in the Yucatan region were at one time above sea level and were dry or partly dry.

Evidence of early human inhabitants and extinct fauna have been found inside some cave systems. Relics of Mayan culture, whose descendants still populate the peninsula, have also been found in the caves.