Updated 19th February 1999; 23rd February, 7th October 2001; 12th May 2002; 19th January 2011; 9th February 2016; 21st September 2018; 13th June, 13th November 2022

   The grid reference above is for the bottom lip of the shaft. A previous GPS (ETRS89: 30T 0.449.024 4.793.463) was above the top edge.
   A large (20 x 5m), choked shaft first descended in 1959 by the Spéléo-Club de Dijon, then in 1988 and 1989. An entrance drop of about 100m meets a boulder slope. Triple checked out by the Catalans in 1995, to find the same choke of boulders. According to Simonnot G, 2018 the chamber at the base are in the shape of an "8".

References: SCD Sous le Plancher; Kendal Caving Club and Manchester University Speleological Society, 1975 (survey); Corrin J S and Smith P, 1981; Fernández Gutiérrez J C, 1975; Ribe G et al, 1982 (survey); Degouve de Nuncques Patrick et Simonnot Guy, 1989; anon., 1995c (logbook); García José León, 1997 (survey); anon., 2001c (Summer logbook); León García José, 2010 (Volume 1 and Volume 2) (survey and photos); Simonnot G, 2016; Simonnot G, 2018; Simonnot G, 2022
Entrance picture : yes
Underground picture(s):
Detailed Survey : from Ribe G et al, 1982 plan and sections from 1976 visit : plan and section from León García José, 2010 (partial copy from previous reference) (Volume 1 and Volume 2) (Cantabria Subterránea - Catálogo Grandes Cavidades)
Line Survey :
On area survey :
Survex file : reconstructed from Ribe G et al, 1982