Aven du Bois de Bouisse

The entrance, 3 x 1.5 m, takes the form of a shaft that is inclined at the start. At the bottom of the shaft (23 m), a short narrow passage gives access to a P22. At the bottom, a short drop followed soon by a second one of 3 m lead to -76 in a chamber at whose level the cavity divides into 2 distinct networks.

Two openings pierce the floor of the chamber and end a little lower in the same small chamber. Lower down, a succession of small drops leads to -123 in a dead end. 15 m before this terminus opens a joint-controlled drop (9 m) followed immediately by a second of 12 m. A sloping gallery leads quickly to the lowest point (-153), which varies with the water level.

In the continuation of the chamber, two small drops lead into another small chamber followed by low passages. From there, a wide, very steep gallery with a rather winding route descends to a succession of drops and passages between blocks. One is then stopped at the same level as in the previous network, at a sump.

The presence of water at the bottom of the cavity is due to the dam and the artificial lake of Avene; it had not been reported by the first explorers.

Belay on the beech tree. At -6, a rock spur allows the rope to be fractioned. At -2, a small rock bridge interrupts the descent; take the narrowest side (right). Take either of the two passages.

The spits of the first 2 shafts are no longer very young. More recent 12 mm bolts have been placed (note, 9 mm caving hangers do not fit).