Aranzadulla

This cave has formed from a joint system with approximate directions 20-200º and 105-285º. No dip of strata is observed.

The final chamber must have formed where two water inflows coincided at that point, one coming from the gallery by which we reach it, which shows signs of activity, and another lateral inflow that appears just at the point where one exits into the chamber, on the left.

The secretary of Zudaire 1975 discovered a large flint deposit (Palaeolithic): some thirty axes and countless pieces of flint. Once these finds had been made, the group of the Institución Príncipe de Viana surveyed the area bordering the cavity, which has given rise to various finds of interest (Archivo Histórico I.P.V.).