Tresviso Caves Project

Tresviso Caves Project Gazetter

FT39: Pozo del Compromisso


Area:Mazarrasa Mines
East, North:360652, 4785718 (nearby)
Coordinate Quality:GPS
Long, Lat:-4.7154916078178, 43.211359442499 (map)
Elevation (m):1820
Length (m):291
Depth (m):-180
System:Sistema Ramazosa
Active Lead:
Survey Available:


From Caseton de Andara, follow the markings for the Pozo de Andara (Lake Depression) /Lake Depression. At the obvious junction (before reaching the lake area) take the left hand path that zig zags up the side of the mountain, until the obvious mine area (Minas de Mazarassa) is reached.


From Caseton de Andara, follow the markings for 40m. After the track takes a hairpin bend a big shaft (5m in diameter 15m entrance pitch) should be visible on the left of the track next to a ruin Entrance


The entrance pitch is a P15 to a snow-plug, and a short passage to a P16, which to achieve a free hang it is necessary to re-belay just below a huge boulder held up by 2 rotten beams, with a level entering above, caution is advised.

Part way down the pitch a potential level leads off but has not been explored.

At the base of the pitch is a large cone of mine debris in a passage of 2m x 3m which descends rapidly. In two places there are rotten wooden ladders which should be handled with precaution. On the right is a large passage, which leads to a network of mine levels connecting back to FT40.

For roughly 30m the passage is horizontal before climbing back to the top of a P18, the base of which is choked.

Just before the passage rises, on the left, is a scramble to a small P6 (split into 2 sections) is followed by a P12, Adrenalin Pitch, which has a loose take-off and is hard to rig.

A P5 and P4 in a rift which is around 70cm wide and 30m long, before widening to a 4m diameter P12 shaft.

At the base of this pitch is a squeeze that has been dug out, followed by a small chamber with an aven that is unexplored. A second dug out squeeze follows, to a 4m climb, followed by the last P17 pitch. An unexplored aven is above but at the bottom of the chamber the passage quickly becomes too tight.


Sefton, M. (1984). "Cave explorations around Tresviso, Picos de Europa, Northern Spain". Cave Science vol. 11-4:199-237.
Krattinger, T.; Morle, C.; Theron, R. (1982). "Picos de Europa 81". L.S.D. - 2:47-81.
T.C.P. (2015)