Las Gemelas

A small mud ramp drops onto a small shaft of about three metres. Below this is a small chamber, its floor entirely covered with humus deposited on a plug of blocks that obstructs the way to the main shaft. An impassable fissure hinted at a possible continuation. A chimney lies above and, after a descent of about eight metres, the dimensions of the shaft increase considerably. A pendulum at minus thirty metres leaves one on a ledge that separates the main shaft from another parallel one of about twenty-seven metres, which ends in a plug of blocks below a ramp heading towards the main shaft. Continuing along the main one, at minus sixty metres one reaches a ledge formed at a change of materials with horizontal strata. From this point, where the dimensions are greatest, the morphology changes to enter a joint that narrows progressively and, at minus eighty metres, a ledge and some blocks leave a small passage giving onto a three-metre downclimb. This leads to a small chamber, a widening of the joint, at whose bottom there is a narrow crawl that gives onto another shaft of twenty-five metres, very clean and with clear solutional formation, at whose base there is a window through which the bottom of the pit is reached, a circular chamber with an impassable meander.

The wire fence was jumped and the doline located. A pneumatic hammer and a generator were hired and, after twelve hours of chipping without rest, the fissure was widened to twenty-two centimetres, just enough to allow access to the main shaft. The small shaft of about three metres was descended by opposition. On the ledge at minus sixty metres the shaft was split into sections.