A gaping maw in the earth. That’s the Abisso della Cava Faccanoni. This is no ordinary hole. This is a 150.5-meter-deep abyss. A testament to the power of nature. And human intervention.
The Abisso della Cava Faccanoni. Its name echoes the quarry. Its history begins in the spring of 1964. A mine explosion unexpectedly revealed the entrance. The blast brought to light this significant abyss. It was remarkably close to the surface. Its location is precarious. The quarry’s expansion threatens to destroy its entrance. It will seal the chambers below.
Picture this. The entrance. A jagged wall of broken rock. A challenging climb. You reach a small vestibule. Above a tiny second entrance. Originally blocked by rocks. A meandering fissure leads down into a pothole. The walls are lined with sharp blades of rock. It widens dramatically. A descending tunnel follows. Covered in fascinating formations. It opens into a low chamber. The floor is a mixture of clay and loose rock. Several holes lead to a second pothole. After a couple of meters you find a convenient ledge. An excellent staging point for the descent. A 67-meter drop awaits. Vertical smooth walls. Yet they are lined with sharp and potentially unstable rock. This pothole is along a fault line. Its base is a cylindrical chamber. About two meters across. From here two branches extend along the fault line.
One branch is a narrow 4-meter pothole. Then a short horizontal fissure. Leading to another 12-meter pothole. It ends in a narrow passage. A short drop marks the end of this path.
The other branch is the continuation of the abyss. It begins with two small drops. Just under two meters each. They lead to a 25-meter pothole. Access is through a narrow passage in rough rock. This pothole appears to be carved by rushing water. Currently only a trickle flows down the walls of the large pothole. The water is from infiltration.
The abyss continues. It descends steeply into a narrow passage. A small drop leads into a chamber. On one side a pool of crystal clear water. On the other a small pothole. The trickle becomes a small waterfall. Access to this 5-meter pothole is difficult. A narrow passage restricts entry. At the bottom the water disappears into impassable cracks.
The Abisso della Cava Faccanoni. Its origins are a small stream. Its action is evident to the entrance of the large pothole. Discontinuities in the limestone allowed for rapid absorption of the water. The fracturing of the rock. It’s a calcareous sandstone with nummulites and alveolines. It causes significant percolation in the deeper parts. This results in rapid disintegration of the walls. Greyish sand deposits accumulate.
The existence of this abyss provides insights into the karst system. Previously the nearby Abisso dei Morti was thought to be unique. A dye test was done. It was hoped to establish a connection to the Teresiano aqueduct of San Giovanni di Guardiella. The results lack certainty.
The Abisso della Cava Faccanoni. A hidden world. A testament to nature’s power. A reminder of the fragility of this underground treasure. Don’t forget your helmet.