Updated 1st October 2006; 28th September 2007; 12th May, 4th October 2011; 15th September 2013; 14th October 2016; 20th May 2017; 21st September 2018
The bottom entrance is at the end of a dry stream bed. The top entrance is in a brambley shakehole 20m behind. Both entrances can draught out strongly.
The cave is basically developed on two levels - the lower stream level soon
degenerates into a two dimensional maze of cobbled crawls. Twenty five metres
inside the bottom entrance a crawl off to the left unites with the higher
level. Emerging up through a rift, past animal bones, the top entrance, a 7m pitch is 5m to
the left. To the right various shuffles and crawls lead to a large chamber
with three exits. All routes appear as a maze and connections can be made
with the lower series.
A frustrating cave, as its position and draught indicate a large amount of unexplored passage. In the summer of '94 a resurvey of the cave could only find 45m with no draughts, confirming what seemed to be the case in 1990. The cave was re-explored in 2006, but again only about 40m was found, but there was a draught at a small dig.
Neither was all the passage refound in explorations at Easter 2011, but a small extension was made immediately to the left of the entrance. This runs upstream parallel to the hillside and was pushed through 2 squeezes to a larger section that becomes too tight in one direction and chokes in the other. One branch comes very close to Cueva Fresnedo 2. This added 44m to the length. The new total length was recalculated from the old and new line surveys (and not an estimate made in the past of passages entered but not surveyed). [The new passage has been drawn up and can wait for a full re-exploration / re-survey.]
Extensive explorations in 2013 confirmed that the cave had collapsed at the end of the higher level rift, just after the short traverse. A dig at this point should access the remaining passage. Annotated sketches can be found in the logbook, 22nd July 2013.
More exploration took place in the streamway in August 2016 but it is unclear whether the approximately 30m of passages dug into are new or just filled-in routes that have been re-excavated. (Sketch)
The entrance to the 8km long Cueva Fresnedo 2 (841) is a smaller entrance 10 metres away. Both entrances are shown here.
References: anon., 1978 (logbook); anon., 1979 (logbook); Addis F et al, 1979; anon., 1980a (logbook); Corrin J et al, 1981b; Corrin J, 1980; Mills L D J, 1981; Corrin J S and Smith P, 1981; material in file; anon., 1990b (logbook); anon., 1994b (logbook); anon., 2006d (summer logbook); anon., 2011b (Easter logbook); anon., 2013d (summer logbook); anon., 2016c (summer logbook); anon., 2017b (Easter logbook); anon., 2018c (summer logbook)
Entrance pictures : yes
Underground picture(s): 2011 : 2013 : 2016 : 2018
Detailed Survey : graph paper drawing from 1980 : 2011 extension : sketch from summer 2016
Line Survey :
On area survey :
Survex file : yes (Easter 2011) (Amended magnetic declination December 2013 to align with Eur79 grid and coordinates altered to fit ETRS89 datum, April 2014.)
caves surrounding this site (Easter 2011) (Amended magnetic declination December 2013 to align with Eur79 grid and coordinates altered to fit ETRS89 datum, April 2014.)