Isturitz is the upper cave. 20 metres below lies Oxocelhaya, and 15 metres below that, Erberua: these three caves are situated one on top of the other in the hillside at Gaztelu, in the Arbéroue valley .

Millions of years ago, the Arbéroue river flowed over a plateau at the top of the current hills.
The water ran down fissures and gradually dug out parallel cavities. The river bed still runs through the lowest, Erberua. It is reserved for scientific research.

The first inhabitants, 80,000 years ago, were primitive tribes (Mousterians). They fought cave bears for the right to live in the upper cave, Isturitz. In a freezing climate, the decimated hordes fought mammoths, woolly rhinos and bisons...

20,000 years later it was the turn of the Aurignacians: standing tall and upright, they are our direct ancestors - Homo Sapiens Sapiens. They engraved and painted animal shapes. Experienced bird hunters, they developed an industry using flint and bone: they made blades, scrapers and polishing objects. This heritage is currently being investigated during a three-year dig campaign designed to expand our knowledge of Cromagnon man in western Europe.

There are many remains from the Gravetian period (27,000 years) at Isturitz. The main chamber with its spectacular concretions hosted whole tribes over long periods and their $$homes (foyer) appear well-preserved. Tools were becoming more developed (chisels and nails). Weapons you could throw first appeared. The cave dwellers' aesthetics were developing, with geometric decorations and the creation of necklaces.