Monte Ferru represents the largest volcanic formation in Sardinia. It is found in the territories within Cuglieri, Santu Lussurgiu and the locality of La Madonnina. It stands out from the landscape for its evocative naturalistic configuration: the western side has imposing walls of dark basalt that plunge into the sea in the Golfo di Oristano. the eastern side gently slopes down toward the highland of Abbasanta dividing into two the centre-west of Sardinia. It reaches a height of 1050 meters on Monte Urtigu, framed by a series of outcrops of columnar or cupola-form trachyte stone. Among these, Monte Straderis is of particular interest, a dome turned into amphitheatre, of a shining light-colour that contrasts with the brown Monte Urtigu. Not far from here is the rock of Monte Entu, slightly less elevated. The other heights are Monte Petrusu, Armiddosu and Punta Mandronisca. In the valley of Riu S’Abba Lughida flows the waterfall of S’Istrampu 'e Massabari. in the valley of Riu Sos Molinos (that takes its name from the fulling mills that are dotted around the territory), near Santu Lussurgiu is found S’Istrampu de Sos Molinos: a real spectacle of nature, that creates endless watery scenes. Monte Ferru is covered by various woods of ilex, strawberry trees, arboreal heather, thorn bushes, hawthorns, wild roses, rockrose and brooms. Proceeding upwards towards the summits asters, helichrysum and caraway thyme. In some points of the mountain area it is possible to find woods of holm oaks, elms and centuries-old chestnut trees, a luxuriant naturalistic background to the tourist town of San Leonardo di Siete Fuentes. Here numerous springs of mineral water gush out and attract a discreet tourist flow, spellbound also by the beauty of the landscape.