Updated 12th, 21st February 2016

  The resurgence for the Mortiro-Equileña system. The cave was first explored as a resurgence-to-sink through trip in 1974. The first 200m in the water are the most awkward and after 300m a one metre long duck has to be negotiated. The passage continues with wading in places until a boulder pile is reached. The surface is reached by a climb up a 9m pitch or by carrying on in the streamway for a few more metres to emerge in the Hoyo del Mortiro. A wet and sporting cave.
   In November / December 2015 and January 2016, water traces by Peter Smith and Terry Whitaker using optical brightener proved that water from the Orillón system in Matienzo was the source of at least some of the water resurging here. Further details of this trace is found on the Orillonzuco page.
    During an optical brightener test from site 3884, detectors were placed here from 13th February 2016 and checked over the next few days in rising and falling flood conditions. The results were consistently negative. The optical brightener came through at the Jivero 1 resurgence after 48 hours. (The full details can be found here.)

References: anon., 1974b (logbook); anon., 1974a; anon., 1975b (Easter and summer logbooks); Kendal Caving Club and Manchester University Speleological Society, 1975 (survey); Fernández Gutiérrez J C, 1975; Manchester University Speleological Society, 1982 (survey); Mills L D J, 1981; Corrin J S and Smith P, 1981; anon., 1993a (survey); Valero Enrique y Soriano Ángel, 2007; anon., 2015d (autumn logbook); anon., 2016a (January, February logbook)
Entrance picture : yes
Underground pictures :
Video :
Detailed survey : see Cueva de Mortiro, site 5
Line Survey :
On area survey :
Survex file : yes (coordinates taken from 1975 paper survey : with Coverón, CEZ and Esquileña