Wikipedia
Gourgouthakas
Gourgouthakas (; from "small cutting on rocks, in which rain water is collected and from which animals drink water") is a cave located in the Lefka Ori mountains on the Greek island of Crete. It is the deepest cave in Greece, with an explored depth of , and is the 43rd deepest in the world.
Gourgouthakas was discovered in 1990 by the Speleological Mission of the Catamaran team, based in Μontbeliard, France. In 1998, the same group reached the small lake ( sump) at the bottom, at a depth of . The lake has not yet been explored.
The cave is primarily a deep vertical shaft, filled with intersecting arcades and huge stalagmites and stalactites. Due to its configuration, specialized equipment and expertise is required to explore it.