Underground Geodiversity of Italian Show Caves: an Overview

About a fifth of the Italian territory is characterised by the presence of soluble rocks, consisting mainly of limestone and dolostone but also of marble and evaporite rocks (gypsum). More than 50,000 natural caves are currently known in this country, a number that is constantly increasing thanks to speleological exploration. Less than 1% of these caves are equipped for visits, and only 64 can be defined as real show (tourist) caves. In the latter, it is necessary to buy an entrance ticket, visits take place only accompanied by a guide, and the underground trail is equipped with paths, walkways and, generally, lighting systems. The Italian show caves expose a great geodiversity and biodiversity, often accompanied by a considerable historical and/or archaeological interest. The underground geodiversity of Italian show caves is related to the variety of lithologies characterising this territory and to the geomorphological and geodynamic processes that have been active during different geological periods. Important scientific research has taken place in many of these caves, and several of these fragile environments are monitored continuously to verify their environmental conditions.