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):0
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


1st pitch, from the surface, is 15m deep leading to a short passage.
A P16 is reached, which in order to achieve a free hang it is necessry to rebelay just below a huge block held up by 2 rotten beams.  At base of pitch is large cone of mine debris in a passage of 2m by 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 rock(?) to small 6m pitch (split into 2 sections) which is followed by a P12 (Adrenalin Shaft) which has a loose takeoff and is hard to rig.  Two small pitchs of 5m and 4m follow in a rift, from which a 30m long passage (70cm wide) leads down steeply to a P12 of 4m diameter. At the base of this pitch is squeeze that has been dug out, followed by a small chamber with an aven. A second dug out squeeze follows, to a 4m climb, followed by the last 17m pitch. At the bottom 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)