Mezalloz

The entrance of this pit, as well as the shape of the riverbed, is very rounded, due to the intense erosive action of the river that flows through them. The pit descends vertically for 5 metres, at the end of which there is a platform containing a large quantity of blocks. From it starts another more vertical ramp 5 m long by 1.5 wide, which leads to another gallery parallel to the previous one, 6 metres long by 2.5 high and tube-shaped. At the end of this gallery the ceiling descends to 0.5 m from the floor, rising afterwards to 2 m. The direction of this gallery is NE-SW and at the end there are two windows with a NW direction; these give rise to a gallery 9 m long that ends in a descending ramp of 10 m, whose bearing is N.

The conduit of the pit is what gives rise to the Izura spring.

The descent is carried out with a small risk, since the platform located at the end of the vertical descent of 5 metres contains a large quantity of blocks. The bottom of the final ramp is plugged by allochthonous sediments.