The Frasassi cave system is a rare natural setting in the heart of the Marche region which originated from a combination of tectonic uplift  and erosion by the Sentino river that runs through the Frasassi gorge. Speleological exploration was conducted from 1950 to 1980, but some large cavities had been known since the early 1800s. In 1974 a part of the cave was transformed into a show cave, the entrance of which is an artificial tunnel into the Ancona Abyss. The show cave records an average of over 6,000 visitors per day. The hoards of visitors has had no significant impact on the cave microclimate, thanks to its largeness and to three sliding doors in the artificial tunnel.
The Frasassi cave system is one of the best examples of caves with sulphide water circulation and one of the most amazing karst complexes in the world, provided with ad hoc walkways and lighting that enable tourists to experience crystalline wonderland featuring multi-shaped stalagmites and stalactites, shallow lakes and alabaster columns, a thrilling chill and infinite silence where you could hear a pin drop! You will never forget the massive Grotta Grande del Vento, Europe's largest single cavern, so large that Milan Cathedral would fit comfortably inside. A one-hour guided tours are provided all year round, we suggest avoiding visits in high summer as it can get absolutely crammed.