It is not a show cave in a strict sense, since it doesn’t have any real walkways, it doesn’t have a permanent lighting system and protective helmets and suitable shoes must be worn, but none the less it is of interest since it is one of the few caves formed in gypsum (rather than limestone) that can be visited, presenting a fine “textbook” example of vadose morphology, and accommodating a few colonies of bats and an abundance of guanobia fauna, it is a unique place for nature lovers to have an unusual, informative and unforgettable experience.
Dug in relatively recent times by a small underground watercourse in messinian gypsum, which formed just 5-6 million years ago, when the Mediterranean was almost completely dried up by the evaporation caused by the closure of the straights of Gibraltar, it is a complete hydro-geological tunnel, which could almost be entirely crossed by the sinkhole at the spring.
With the exception of the large room that accommodates the abundant cave fauna, situated a little after the sinkhole, it is a long gorge, high and narrow, with wide meanders and magnificent forms of erosion. There are also extensive deep yellow-colourerd calcite flowstones that cover the walls in some parts, almost entirely made up of a tight network of shining gypsum crystals (selenite variety) which reflect the lights of the electric torches. Where the ceiling is flat it gives the impression of being under a starlit sky.
The path is made up of an uninterrupted line of garden floor tiles cm. 40X40 placed on top of a strip of cement a few centimetres thick which runs along the centre line of the gorge’s floor. No handrails: you lean against the walls, always close to one another, but not enough so as to avoid putting your foot off the path if distracted. The lighting is provided by modern LED frontal lamps fixed onto helmets which are are obligatory for visitors. Everywhere it can be noted where work has been done to put into safety (by means of big pillars and large steel ropes) the unstable blocks of rock and the enormous embedded blocks of rock which in various parts make up the ceiling of the tunnel.
The choice to equip it as a semi-show cave puts this cave in a prominent position in its category. Given its conformation a fixed lighting system would not permit the more interesting features to be enhanced and could distract the attention from watching where you put your feet and put your safety at risk. Also the construction of a real walkway with railings would appear too invasive.
It is better to have an excellent semi-show cave, like it is now, rather than a show cave that would end up disappointing a clientele which for the most part comes here after having visited the nearby Frasassi cave or other natural caves which are better equipped and more spectacular.
The very good guides provide valid information about the biology and zoology of the big park outside, as well as illustrating passionately and competently every aspect of the cave, both from a geological and morphological profile, as well as a biological one.
In a small cavity situated a few metres from the sinkhole a small gem of mineral archeology can be seen: an old workshop where the gypsum extracted nearby was baked in special ovens and ground in a big millstone. A little higher up, along a carriageway, a vertical shaft communicating with the cave emits in Winter a hot air current inside the cave.
Outside there is a big car park, and in two distinct buildings, a visitor’s centre with a gift shop, a meeting room, and a well-kept museum with models, dioramas and large panels with explanations where the main theme is bats. External facilities that many show caves would like to have.