Prenuragic area of extraordinary importance and the largest in Sardinia. It is located nearby I Piani, along the county road 42, not far from the airport of Alghero-Fertilia. It was discovered by chance in 1903, during the excavations for the building of a farmhouse. The finding of some human bones encouraged further excavations, until crockery, jewels and several hypogean graves were discovered. Over the years, a total of 38 Domus de Janas (Home of the Fairies) were discovered, along with underground graves dating back to three different historic periods: the civilization of Ozieri (3500 B.C.), of the bell-shaped vase (2000-1900 B.C.), and of Bonnanaro (1800 B.C.).