Aven de la Bise n°1

Bise 1 is mainly a succession of relatively narrow small shafts, unlike Bise 2, which is a fine large gassy shaft. Bise n°1 opens vertically. The first metres are easily down-climbed; equipment is optional. From the bottom of the R29, many spits are no longer usable; AFs generally make up for this. The term “pendulum” in the P30 is misleading: there is not really any penduling to do, it is mostly about finding the right passage among the blocks suspended in the diaclase; it would be useful to put a piece of scotchlight there.

At the start of the river, passage through a chaos of blocks with the odd narrower passage. Then you progress mainly by opposition, it is fun and the water is beautiful. Towards the end of the river, a fixed MC above the water is completely frayed (08/2026): it is nothing more than frayed strands at the AN it surrounds; this is very visible when doing the traverse from Bise 1 to Bise 2, it is more treacherous in the other direction.

In the case of a cross-through traverse, the wait will be much longer for those going from Bise 1 to Bise 2: a lot of rigging then few fractios to climb back up; define the size and composition of the teams accordingly, as well as their respective departure times. Cairns and flagging tape are present in abundance from the start of the river. Several fixed ropes exist (small climbs, securing of certain oppositions).

Given that we did not find a rigging topo (the 2008 one is largely outdated), I note what we used in 08/2026 to give an approximate idea, because it will always be better than an empty page. There is certainly a way to rig differently, and better! Some of the ANs were not great. We needed about 20 dyneemas.