El Cubion

Took the divers down to both tie in the existing survey and explore the sump. Unforunately the disto did not work so no more surveying was done. The sump proved to be too dangerous for Mark's liking due to undercuts and no belay points so he turned around where the air space ran out. We then looked at the upstream climb, finding larger passage with some red and white tape, which must had fallen down from above (an easier way down?). The passage ended at a short drop (rope required) into a small chamber and a very deep slot in the floor with distant rumbling below.