At the base of the Exotic Garden's cliff (called “the observatory” after the small astronomical observatory once located there), at 100 m in elevation, opens up an underground cavity which has been fit out for visits. The calcareous rock was hollowed out by water rich in carbon dioxide and is full of caverns complete with amazing concretions: stalactites, stalagmites, curtains, columns, spaghetti-like helictites, and more.
The cave tour is included in the price of entrance to the Exotic Garden and is given by specialists. It goes from 98 m to 40 m in elevation (approximately 300 steps). The cavity descends nearly to sea level and a favourite spot for local spelunkers.
The presence of prehistoric humans in the area around this cave can be proven by the bone remains of the animals that provided their food. These remains are also proof of the climatic variations of the past 250,000 years.
The Prehistoric Anthropology Museum is an excellent destination when combined with the cave visit.
