3649: Casa Vieja, Cueva de la
Moncobe 30T 446238 4796966 (Datum: ETRS89. Accuracy code: A) Altitude 246m
Length 318m Depth 126m
Area position

Updated 28th September, 9th October, 29th November 2012; 30th April 2013

   The entrance is an obvious 1.5m diameter opening in the right side of a low cliff in the second wooded gulley from Casa Vieja farm just before the gulley opens into an amphitheatre. The entrance usually takes an inward draught.
    A short crawl leads to a 3m drop best descended by a short ladder. A roomy L-shaped chamber leads down to an undercut which degenerates into a 5m long crawl with leaves and other flood debris. The water evidently comes through boulders under the gulley in wet weather. The crawl ends in a sediment blockage. The blockage is bypassed by climbing a short, excavated climb at the end of the chamber leading to a 3m climb down a small rift. This leads almost immediately to a 4m pitch (artificial anchors) into a roomy chamber that takes the water in wet weather. Twenty metres of easy passage leads to 14m pitch (artificial anchors) into a high, clean-washed, 8m diameter chamber at the far left side of which is an upslope in a rift, filled by large hanging blocks. In the left wall of the chamber below the 14m pitch is a tight crawl leading to a draughting aven and a 5m pitch. The base of this has two passages, one 3m long to a blind chamber, the other 7m rising to two boulder-filled, choked inlets. (Not in surveyed length.)
    On the far right side of the chamber the rift continues down a steep slope of very loose boulders for 20m. It levels out on sandstone ledges over a 4m long hole below which is an 85m pitch. The rift above the pitch may be followed for about 10m under a fallen flake to a flat-out crawl on wet mud to a point where it becomes very tight. This has been pushed 4m to the head of another ‘large’ 4-to-6-second-drop pitch.
    The 85m pitch leading into a 10m circular shaft can be descended via artificial anchors to a flake-and-sling deviation about 35m down and then two Y-hangs to a clean-washed cobble strewn floor with no outlet. A 5m climb up from a fallen flake leads to a mud-floored saddle with artificial anchor for the next descent. About 20m of a series of offset drops all covered in wet mud leads to 5m of low passage with a mud-pool floored outlet that is too tight.
    A bolt route down the left side of the 85m pitch of about 40m leads to a swing into a rift, the roof of which was once a phreatic tube. The original tube can be seen continuing at the other side of the shaft, it appears to be open and about 1m high. The rift/tube runs approx east-west. To the east, up the rift, a cobbled floor can be seen which is probably under the hole found at the end of the low tight crawl pitch. The passage appears to be wide open and continuing and more bolting is required.
[Description by Alf Latham; additional material, November 2012]

The bolting project was taken on at Easter 2013 and passage entered on the west side of the 85m pitch. The passage was traversed over a rock bridge and a 6m pitch dropped into an area of large rifts with further pitches down, some estimated to be 20m and large enough to descend. The site requires a high level of SRT skill and is not for novices.

Reference: anon., 2012b (Easter logbook); anon., 2012e (autumn logbook); Corrin Juan, 2013a; anon., 2013b (Easter logbook)
Entrance pictures : yes
Underground pictures : yes
Video :
Detailed Survey : plan and section : sketch of 40m climb down to continuing passage, autumn 2012
Easter 2013 - survey in preparation
Line Survey :
On area survey :
Survex file : yes (after Easter 2013) (Amended magnetic declination December 2013 to align with Eur79 grid and coordinates altered to fit ETRS89 datum, April 2014.)

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