Sepulturas de Zigantes or de paladinos, as the inhabitants of Luras called the dolmen (from the Breton tol-men, being stone table), the funerary monuments built as of the late Neolithic period (3500-2700 BC), are found in greater concentration in these areas than anywhere else on the island. Here there are four of the 78 in total in Sardinia, located within the town or in its immediate vicinity. There is the allée couverte di Ladas and the simple-structured dolmen of Alzoledda, Ciuledda and Billella. Made according to a trilithic system – horizontal slabs supported by other vertical ones – they served the function of collective burials and, together, of a place of worship, compared with similar examples of Basque, Catalan, French, Corsican and Menorca origin.