In the 4th century BC the first evidence of stable settlements appears in the Guadiana river basin. This period is called the Chalcolithic, and is characterised by burial of the dead in dolmens, funerary chambers made from huge stones and covered by a mound. A scarcity of luxury goods has led experts to interpret their society as basically egalitarian.

Besides dolmens, extensive settlements protected by moats have been found. These were built by farmers who exploited a wide range of resources and materials. They began to produce copper objects, and established extensive routes for commercial exchange.