Trou du Faucheur

Once past the entrance, you enter a pretty E/W conduit 30 metres long with a joint fissure rising to + or - 0 m. The continuation is at 90°: it is a phreatic tube where you progress on all fours, cut by several perpendicular joint fissures. After 50 metres, you reach a perennial body of water (80 metres from the entrance), called the “lake”, 15 metres long, shallow but which, given the height of the gallery, requires almost complete immersion.

You emerge into a tall joint fissure followed by a new crawlway and another joint fissure extended by a low, muddy conduit that leads to the foot of a step. Once this step is climbed, you reach a pretty overdeepened joint fissure that leads to a new bend at + 0.5 m. The continuation is a long crawlway running almost N/S, embellished after 50 metres by a joint fissure that leads into a small upper chamber (start of a meander to the East) which constitutes the high point of the cave (+10 m). The crawlway continues after the joint fissure and then rises a little towards the end where it is blocked by the concretion at + 8 m.

The cave presents itself as a long phreatic tube intersected by perpendicular joint fissures. Most of the galleries are carved along bedding planes (syngenetic phreatic tubes); the transverse galleries of limited extent are carved along joint fissures and are of vadose type, most of them being later than the carving of the main gallery. The network appears to be an ancient underground course parallel to the surface stream, of origin to be sought 400 to 500 metres further north. The cave continues beyond the lake for 200 metres up to elevation +8.

In summary, an interesting and wild cave with very beautiful gallery shapes.

During fillings (doubtless very rare) of the cave following heavy rains or floods, the gallery certainly floods from the entrance to the step, thus over about 150 metres. At 80 metres from the entrance, you come up against a lake which may siphon depending on the time of year; it measures 15 metres long and can be crossed at low water without diving.

Geology: compact lacustrine limestones with stylolites of the lower Thanetian.