ABSTRACT
The Frasassi Caves are located in central Italy, on the eastern slopes of the Apennines some 40 km from the Adriatic. They developed in a small anticline ridge deeply dissected by the Sentino Gorge (Figure 1). The caves constitute one of the most famous Italian karst systems, partly because they host the most-visited show caves in the country. Speleological explorations of the area took place mainly from 1950 to 1980, but some large cavities have been known at least since Procaccini Ricci’s 1809 Memoria sulla Grottadi Frasassi nei dintorni di Fabriano. The Frasassi system is of particular scientific interest, and is presently one of the best examples of a cave with sulfide water circulation: in its lower branches, hyperkarstic speleogenetic mechanisms are active, and an unusual ecosystem dominated by chemiosynthetic organisms has been documented.
