The Lastra hill forts are located on a hill within the boundaries of the villages of Caranca and Cárcamo.

The site occupies the upper-middle part of the hill on which it stands. Its northern side is defended by a steep, rocky escarpment that is difficult to access, except for two small openings that may have served as passageways since the time the settlement was inhabited. This natural protection is complemented by an artificial wall that encircles the settlement from east to west.

Around 1200 BC, a group of people, mostly from the valley below, settled on the middle part of this hill. These first inhabitants adapted part of the hillside for their dwellings and areas dedicated to livestock and agriculture. The houses from this first phase were built with timber framing covered with mud.

Around the 5th-6th centuries BC The greatest boom and expansion of the town occurs. The old circular houses will give way to rectangular ones, which will form an urban layout of attached houses, aligned on both sides of a street paved with small stones.