Abisso dei Grassi Trichechi

The part down to -70 m is characterized by chaotic landslide environments and narrow passages, up to a large, steeply inclined gallery that ends in a landslide. A narrow passage in the initial part of the gallery, lo Scalpo Giallo, leads to a new sequence of landslide environments, rather unstable. Practically from the entrance we are inside a bundle of large fractures, visible also outside, heavily cluttered with boulders of various sizes. The large meander that comes from the right, climbed, stops against yet another landslide, while the shaft, estimated at 100 metres, has not yet been descended. The first bottom is an anonymous fracture that becomes progressively narrower at a depth of 365 m. The uncomfortable meander that follows is, in a cave dominated by tectonics, the first environment entirely carved by the action of water. The way on the left leads to a narrow environment that closes with a small sump at a depth of 475 m. Continuing along the chamber, still set in a high fracture, a second chamber is encountered, of smaller dimensions. A final P5 leads, at a depth of -540 m, to a chamber cluttered with boulders. The PIT II galleries continue for over 400 m in a SW direction, alternating vadose environments, phreatic conduits and a series of short shafts; the route, straight and without significant variants, becomes complicated toward the bottom: an unstable climb on the right leads to a large chimney (8x40 m), il Bello ma Inutile, while the main way is lost in a tangle of narrow passages and mud blockages. The Gallerie Marilena are ancient conduits, 150 m long, that retrace, a few tens of metres higher, the route of the cave below. An orthogonal fracture forces a dry detour to the right for 50 m of uncomfortable progression, interrupted by a selective squeeze. A new fracture, again orthogonal, allows one to reach a new gorge.

At the bottom of the chamber at -540 m one glimpses the stream flowing, heading toward Piaggia Bella, which runs through the last parts of the cave. At the base of the large P60, following a small watercourse one reaches a series of chambers.

A P5 and various climbable drops are the prelude to a new steeply inclined gallery that leads, after a short climb, to a stretch of horizontal gallery, followed by a second climb (15 m). At the climb, above, one glimpses the arrivals of meanders still to be reached, while ahead several alternatives present themselves: below begins the long series of shafts that leads to the bottom, while ahead a traverse leads to a gigantic environment that offers further forks. A little further back, the route to the bottom presents a couple of short shafts (P5 and P20) that lead to the following P110, which is the greatest vertical of the cave. A rapid sequence of shafts (P15, P25, P20, and P10) leads to the first bottom. Traversing a little beyond the middle of the P110 one reaches a new series of shafts (P10, P20, P52 and P19). Immediately after, a P32 and a P27 lead to a fissure followed by a large chamber that offers a new fork. The way on the left, a small climb followed by a P15 and a P20, leads to a narrow environment. A passage between boulders in the floor leads to the base of a new shaft which, if descended, connects to the route to the bottom of -475 m. Traversing this last vertical one reaches a narrow crawl, some tens of metres long, that opens, finally, into a large fossil meander dedicated to the Mexican writer Paco Ignazio Taibo II (PIT II). To his father, also a writer (PIT I), is dedicated instead the upstream part of the meander, a conduit that develops for about a hundred metres up to a gigantic ascending shaft. The PIT II galleries, swept by a noticeable air current, continue for over 400 m in a SW direction. Traversing at the top of the third-to-last small shaft of the PIT II one reaches the Gallerie Marilena. A new fracture, again orthogonal, and a P15 allow one to reach a new gorge swept by a very violent air current. After 70 m a 15 m climb leads to a short gallery immediately interrupted by a large P60 at whose base, following a small watercourse, one reaches a series of chambers. In the last of these chambers, through a short fracture, suitably cleared, and a subsequent P5 one reaches the meander Réseau E di Piaggia Bella.

A crucial cave that, despite the elevation of its entrance, behaves as a low entrance, the Trichechi still boasts great exploration possibilities: the cave offers numerous anomalies in its initial parts where a fortunate climb could put it in relation with the numerous drafty holes present on the northern side of Pian Ballaur or, with some optimism, with the southern one of the Saline. Over the region moreover dominates the great question of the position of the watershed between the system of the Foce and that of the Pis dell’Ellero which, through climbs or the descent of the large still untouched shaft, the Abisso dei Trichechi could help to understand. The cave becomes extremely dangerous in caso di pioggia which makes the shafts impassable.