Consists of a single gallery of highly variable cross-section along its passage. About 30 metres from the entrance, a much wider chamber begins, slightly elevated above the entrance gallery and with its floor covered by a large quantity of blocks; on the right, a low-ceilinged gallery branches off and becomes impassable within a few metres of passage. In the N sector of this central chamber, and after climbing a small step, one enters a gallery of very reduced cross-section that continues for about 25 metres until it is closed off by a chaos of blocks.

Along the passage of the gallery in the N sector flows a small watercourse that is lost in the central chamber.