Updated 18th February 2012; 6th September 2019; 13th May 2025
The entrance is a resurgence at the head of the wooded valley behind the old Fuente
las Varas Bar, although it couldn't be found in August 2019 due to an approach through heavy vegetation to the top of the cliff.
The whole of the cave is stooping or crawling in water and
the previous "end" (up to April 2025) is where the going becomes flat-out. This point is approaching
the painted flag on the Fuente las Varas crags and one or more of the resurgences
around the cliff may well be the source of the water. (A dye test has shown
that the water resurging from site 0101 has no connection with
Cueva de Fuente las Varas). The cave appears on the Cueva Hoyuca and the Four Valleys System Hydrology diagram.
The stooping-sized cave entrance turns left to a small dam and immediately
afterwards a waist deep pool with a silt floor is past to a stream passage
which is mostly comfortable crawling or stooping, with one rift where it
is possible to stand up. Exploration in 2001 appeared to stop a few metres
short of the 1977 limit, in a pool with the way on very low.
The cave was pushed, extended and surveyed for an extra 41m at Easter 2025.
From the old 'final' chamber, there are two continuing passages.
First, the excavated entry to the left-hand El Gordo Branch, which is the main source of the water in the cave. This is a low and wide bedding plane, half full of water. It has an extremely encouraging draught. The passage goes round to the left to where it very nearly emerges in dry passage. However, the way is blocked by a jelly-like barrier of saturated mud. This will need some persistent bicycle kicking to liquify and proceed. However, it does look like there is a little more space ahead. A return is planned in the summer 2025 to continue pushing this passage.
The right-hand Rocky Horror Branch was pushed beyond the earlier limit. This took the form of a low phreatic canal, with a fluted ceiling. There was very little or no draught here. After 50m or so, it was possible to roll over onto one's front and crawl for the final 5m, until a little moonmilk cascade was met, with a calcite bridge across the passage. A small triangular hole continues over and beyond the cascade, but the moonmilk / calcite floor would need a fair bit of digging to make progress. The lack of draught in this passage strongly suggests the El Gordo Branch is the lead to push.
References: anon., 1977b (logbook); Corrin J S and Smith P, 1981; material in file; anon., 2001a (Easter logbook); Corrin Juan, 2003a; anon., 2019d (summer logbook); anon., 2025a (Easter logbook)
Entrance picture : entrance : 2001 resurvey and photo team
Underground picture(s): from 2001
Detailed Survey : 1:1000 : Easter 2025 (interim survey)
Line Survey :
On area survey :
Survex file : 2001 (Amended magnetic declination December 2013 to align with Eur79 grid and coordinates altered to fit ETRS89 datum, April 2014.)
Easter 2025
Hydrology (Terry Whitaker): Hoyuca and the 4 Valleys System
