Updated 5th November 2011; 5th December 2013; 5th January 2015; 11th February 2016; 24th September 2018; 17th November 2022

According to Simonnot G, 2016, the site position is ETRS89 0446916 4792435.

A cave at Bustablado (and hence out of our caving area) with a number of sumps. French cavers are actively exploring the site. Downstream has reached a considerable depth and split. Upstream may be the inlet from Torca del Hoyón and downstream may continue to Cueva Molino. Further details can be found on the Cueva Molino page.
Some info is found on the Cuevas del Asón blog.

The information below has been roughly translated from the French, Spéléo-Club Dijon reference, Simonnot G, 2016.

1980 - The loss of Bustablado stream at a place called Orcones was spotted in August 1980 by G. Simonnot. Only twenty-nine years later further investigations take place (see Sumidero de Orcones 2, SCD2035 / MCP4279)
2009 - July: The small entrance is discovered only fifteen meters from the stream sink. After rapid enlargement to make it practicable to -10m hard unblocking (nearly two hours) driven by the draught, strong on a summer day, allows access to Munke Gata (-30m). About 250 m length.
   August: Topography and exploration of a meandering tributary. Length 300m.
2010 - July: Diving the downstream siphon by Manu who goes 200m in total and over the upstream siphon by Yann, 120 m. An draught blowing up in the small gallery before led to Munke Gata. Length 650 m.
Topography of drained parts of the southern branch discovery and return of a branch heading eastward in the southern siphon Munke Gata. Length 950m.
Diving following the east siphon 160 m further to -30m. "Freeze lack of autonomy"? Length 1,110 m.
2011 - April: "Equipment turns Hazel"?
   July: Diving upstream: additional 30 m only (low point -23m) due to the fill forming a crawl 20 to 25cm high. A passage to the right to inspect. Diving downstream is 465m long in total, "spring"? after 440 m (80, 200, 160) (low point -30) in an airbell. At this level some dry land above water meander through which a trickle of water could be raised on the left bank of 200 m. Downstream of the siphon airbell continues (diameter 5 to 6 m).

Link to entry in the Cave Diving Sump Index.

Reference: anon., 2011d (summer logbook); anon., 2011e (autumn logbook); Papard Philip, Corrin Juan and Smith Peter, 2014; Simonnot Guy, 2014; Simonnot G, 2016; Simonnot G, 2018; Simonnot G, 2022
Entrance picture: November 2015
Underground pictures :
Video :
Detailed Survey : part plan (2010)
Line Survey :
On area survey : on Matienzo Caves map : from Guy Simonnot after French divers summer explorations
Survex file : partial (Coordinates altered to fit ETRS89 datum, April 2014.)