Aitzarrateta Spring. Source of the river Ertzilla

The area of Iribas contains mountain springs, potholes, drains, dolmens and old river courses and is an example of the formations that water is capable of cutting out both underground and on the surface of the limestone mountain.

The Lezegalde Cave traces a network of chambers that leads to a large pool via low corridors with beautiful ceiling and floor formations.

There is a booklet available from the Consorcio Turístico PLAZAOLA which sets out the phenomenon of this river and the signposted route.

Available from the Consortium’s shop, entitled "La senda del Agua".