059 Cueva del Molino (Cueva del Agua) (Pozo de Guzmartín)
Enaso 30T 451618 4796237 Alt. 163m Length 1968m Depth 12m

Updated 19th February 1999; 3rd January, 26th October , 12th November 2001; 7th June, 11th November 2002; 14th October, 8th, 26th November 2003; 21st November 2004; 8th November 2006; 25th February, 27th September, 28th October 2007; 26th September , 20th December 2008; 29th October 2009; 6th January, 4th November 2011

The sink for all of the water in the Vega branch of the depression. The cave provides an interesting wet trip.

An impressive entrance at the end of the stream bed leads to a large, rock-strewn chamber at the end of which the water is met. The remainder of the main line cave is sporting stream passage - a mixture of wading, clambering and swimming in large passage. At the cascades, a high rift passage leads off for 60m with calcite flowers on the floor. The large sump pool at the end of the main passage has been dived through to La Cuevona (248), the resurgence.

On the left of the first lake, 200m from the entrance, is a strongly draughting inlet which has been followed for some 600m until it becomes rather small. In 1991 this was extended by some 45m but is impassable. This lies under Cueva de Rascavieja (077) and is heading towards Torca del Mostajo (071).

Just upstream of the sump on the right, are two calcite ramps with fine, coloured formations. One of these holds a deep, blue pool which was dived in October 2002, but led nowhere.

Just after the 3rd lake, on the left, is a 4m climb to a series of small passages, Snails Pace Passage, which rise some 20m above the stream, contains excellent formations and ends too tight or in chambers. The floor is covered in white snail shells, many calcited in, and the river can be heard through a hole in the floor.

At the end of the cave, the left hand ramp contains a puzzling low wall, on which a stalagmite has formed. This, presumably, is the "prehistoric alter" referred to in the Plymouth accounts. There is a discussion, photo and drawing in Ruiz Cobo Jesús and Smith Peter et al, 2001. Ruiz Cobo Jesús and Smith Peter, 2003 has a photo (page 95) and the stal covering the stones has been dated to 10.9 - 35ka BP.

Ortiz in Algunos crustaceous y miriapodas cavernicolas de la Region de Matienzo, Santander (Ortiz E, 1968) records two species, Lithobius derouetae Demange and Gammarus berilloni Catta, while Notenboom in Research on the Groundwater Fauna of Spain: List of Stations and First Results (Notenboom J and Meijers I, 1985) includes Cyclopoidea and Insecta, collected at the start of the Ríotuerto Inlet.

Cavers from Barcelona found a mammoth molar (Elaphas primigenius) in the river passage near the large ramp.

A small decorated copper plate or plaque (discussed in Fernández Ibáñez Carmelo, 2001) and small fragments of pottery were found in the first chamber, to the right of the river. A level with flints also exists under the calcite floor in the same chamber.

Samples of stalagmite were removed from the cave for dating in 1993. According to Openshaw (reference DK), only one of the stals were of use for studies of palaeosecular variation, comparing well with a UK lake sediment master curve. This gave a date of 35ka for a stal 25cm above the stream, indicating rather slow down-cutting.

To the right of the first chamber, a small passage is reached up a short climb. Sections of the roof and left hand wall are composed of a 3 - 4m(?) thick calcited bone and rubble breccia which will prove interesting if dated and the bones identified. It has been suggested that these deposits may be the remains of an ancient hyena den, in use for a long time. After 25m this passage emerges on the surface. Down to the left, a hole drops into 25m of low, dank, choked passage with anastomoses. This area needs surveying.

Some other small pieces of pottery were recovered in 2007 high on the right wall, above the bone breccia passage. These can be seen here.

A programme of water hardness data sampling (photo) was started in October 96. What were the results?

At the end of summer 2006 and into October, the river was sinking 50m upstream of the entrance. The pools on the left of the boulders just inside the cave entrance were completely dry and the water was first seen at the back of the entrance chamber, at the 1st "lake". It appears that the river has (re)opened a low level route and / or water abstraction at Cueva del Comellantes has caused less water to reach Cueva del Agua. Earlier in the summer the water had been filtering away in the river bed about 100m downstream of the Comellantes resurgence. (This point is site 2755).

References: Puig et al, 1896; Fernández Gutiérrez et al, 1966 (survey and photo); anon., 1974b (logbook); anon., 1974a; Cox G, 1973; Fernández Gutiérrez J C, 1975; Manchester University Speleological Society, 1982 (survey); anon., 1975b (logbook); Kendal Caving Club and Manchester University Speleological Society, 1975; anon., 1976 (logbook); Ullastre-Martorell J, 1975 (survey and photo); Smith P, 1985; anon., 1977b (logbook); anon., 1979 (logbook); anon., 1980a (logbook); Mills L D J, 1981 (photo); Mills L D J and Waltham A C, 1981 (survey); Corrin J S and Smith P, 1981; Smith P, 1981b (survey); anon., 1981 (logbook); anon., 1983b (logbook); Cawthorne B, 1984; anon., 1985a (Easter logbook); anon., 1985b (logbook); anon., 1986 (logbook); material in file; Cawthorne R, 1987; Ortiz E, 1968; Notenboom J and Meijers I, 1985; anon., 1988 (logbook); Cawthorne B and Neill A, 1990; Cawthorne Bob et al, 1988; anon., 1989 (logbook); Neill A et al, 1989; anon., 1991 (logbook); Neill Ali, 1991; Corrin J, 1992a; anon., 1992b (logbook); Corrin J, 1992b (survey); anon., 1993b (logbook); Neill Alasdair and Jackson Keith, 1993; Corrin J, 1994a; Openshaw S et al, 1993; Muñoz E and Bermejo A, 1987; Corrin J, 1994b (survey); anon., 1995b (Whit logbook); Openshaw S, 1996 (survey); anon., 1996c (Christmas logbook); Corrin Juan, 1997a; anon., 1997b (logbook); García José León, 1997 (survey and photo); anon., 2000c (Summer logbook); Ruiz Cobo Jesús and Smith Peter et al, 2001 (includes photo of wall with survey); Fernández Ibáñez Carmelo, 2001 (includes drawing of brooch); anon., 2002c (autumn logbook); anon., 2003 (summer logbook); anon., 2006e (autumn logbook); anon., 2007a (February logbook); anon., 2007d (summer logbook); Corrin Juan and Smith Peter, 2007; Corrin Juan, 2007a; anon., 2008e (summer logbook); Ruiz Cobo Jesús et al, 2008; León García José, 2010 (survey and photos); anon., 2011e (autumn logbook)
Entrance pictures : From a distance   At the entrance   Entrance in winter showing the mill race wall  
In severe flood   In moderate flood from above   Second, smaller entrance to the east  Main entrance dry
Underground picture(s): Placing water hardness detector   Looking out to entrance  
entrance in moderate water conditions  entrance in moderate flood  bone and rubble breccia area (2007)  pottery 2007
entrance chamber formations, 2008 : miscellaneous 2009 : entrance chamber 2011

Digital photos, October 2006 by Juan Corrin with Phil Papard (e.g. A3) and Ian Chandler (e.g. C1) A1, 2: Calcited bone and rubble breccia. (More photos of these deposits can be found here.) B2,3: Crystals in dry gours C2: Composite across entrance chamber facing downstream.
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Digital photos by Tim Webber. Click to enlarge.
A1,A3, C3 cave life; A2 tree trunk wedged in stream passage

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Digital photos by Andy Morse A1,2,3; B1,2,3; C1; and Barry Hullatt C2,3 and D1 with members of ISSA. Click to enlarge.

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Scanned slides by Frank Addis (A1, 1980) and Juan Corrin (remainder, taken in 1975). Click to enlarge.
A 1: Looking out from the entrance. 2: The First Lake. 3: Spectacular formation on the last(?) ramp.
B 1: Formations on the last(?) ramp. 2: Formations on the last(?) ramp.

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Video: stream passage 2009 10Mb (Alex Ritchie) : video camera and lights trial in entrance chamber, 2011
Detailed Survey :

1966	known cave	low res	high res
1967	known cave	low res	high res
1975	on area survey	low res	high res

Line Survey :
Survex file : download
Passage direction rose diagram (Patrick Warren): yes