some of europe's largest publicly accessible caverns lie in the cave network gouged out by river sentino southwest of jesi. of the vast network of 18km., an area of about 1000m. is open to the public.
the colossal grotta del vento is large enough to contain milan cathedral, its ceiling extends to a height of 240m. (787ft.).
this cavern has been used for a range of experiments, from sensory deprivation to an exploration of the social consequences of leaving a group of people alone in its depths for long periods.