0472: Piluca, Sima de la
Piluca 30T 451718 4794061 (Datum: ETRS89. Accuracy code: M) Altitude 568m
Length 315m Depth 141m
Area position

Updated 19th February 1999; 14th May 2000; 5th May 2001; 29th October 2009; 8th October 2010

The 5m x 2m entrance, which has a tree just visible on the southern slope of a large depression, is one big pitch with two rebelays, about 120m deep. Passage 15m up from the floor goes to an 18m pitch with about 75m of small choked passages one of which rejoins the main shaft 5m up.

A pendulum reaches the opposite side of the shaft and a passage which leads straight to a 27m pitch with an immature stream flowing across the floor. All obvious ways choke or get too tight. A strongly draughting boulder choke 3m up the far wall has been dug through into another chamber full of loose boulders and a steeply descending mud slope down which boulders fall for about 3 seconds. Needs hammering and digging.

The cave was re-explored, extended downstream and surveyed at Easter 2001 and the description from the logbook needs merging with the old description above. There appears to be a good draught with possible digging sites.

The cave was rebolted and tackled up in the summer 2009, but no new exploration or excavations were carried out.

In 2010 a fresh team re-explored and pushed, providing the following description:

By rigging off two bolts on a boulder, the shaft can be dropped with 7 rebelays and a deviation (rigged with some new bolts, installed July 2010). The landing is on a boulder floor and a muddy 3m climb up is the way on. This is followed by a climb down and a crawl to the base of a pitch that can be entered from the top via a crawl about 20m up the main pitch. From here the cave is essentially a single large meander. There is a crawl followed by a step over a small pot leading to more crawling and a climb up a bit of tat. A short distance later a climb down is assisted by another bit of tat leading to another crawl to the head of the final 10m pitch. This can be rigged off a huge boulder and 2 bolts in the roof.
It lands in a chamber in a sandstone band containing large sandstone bolders. A small stream drops from the roof and flows off into a boulder collapse. Climbing over the boulders one enters a large fossil passage with some nice stal which chokes completely after about 10m. By climbing down through the boulders the streamway is regained which vanishes into a tiny tube.

References: anon., 1983b (logbook); Corrin J, 1983b; material in file; Garcia J L, 1987; García José León, 1997; anon., 2000b (Easter logbook); anon., 2001a (Easter logbook); Corrin Juan, 2003a; anon., 2009c (summer logbook); anon., 2010c (summer logbook); León García José, 2010 (Volume 1 and Volume 2) (photo); Corrin Juan, 2011
Entrance picture : yes
Underground picture(s):
Detailed Survey :
Line Survey : 3D line survey
On area survey :
Survex file : yes (Amended magnetic declination December 2013 to align with Eur79 grid and coordinates altered to fit ETRS89 datum, April 2014.)