In the past, the most important basin on the Island was, for a long time, the largest in Europe and is currently a tourist attraction rich in history and charm. The Omodeo lake stretches for almost 30 square kilometres, belonging to eleven Municipalities in the province of Oristano, in the historical territory of the Barigadu. It is formed by the barrage on the Tirso river: from 1924 until the end of the 20th century the river was closed by the 'historic' dam of Santa Chiara. The barrage designed by Angelo Omodeo for regulating the course of the river, for producing energy and for irrigation, was built in five years by 16 thousand workmen and was inaugurated by Victor Emmanuel III. In 1941, while the Second World War was underway, the dam was attacked by torpedoes from British aircraft. It was replaced by a new one, which was a hundred metres high and 582 metres long, named after Eleonora d'Arborea, built in 15 years and inaugurated in 1997. The previous barrage was partly submerged by the new construction.

The valley covered with water contains an archaeological treasure: Nuragic settlements and the pre-Nuragic one of Serra Linta are under the water together with an ancient fossilized tropical forest, dating back approximately 20 million years, and the evocative little village of Zuri. The village, which was sacrificed when the dam was constructed, was rebuilt upstream, together with the Romanesque church dedicated to San Pietro Apostolo (dated 1291), taken apart and rebuilt ashlar by ashlar (1923). Before the new dam was built, in periods of drought, evidence of the populations that inhabited the Medio Tirso area reappeared. This still happens today: the villa of the station manager recently re-emerged completely and has become a tourist destination. The house and nuraghi emerge with a colour that matches the land because of the silt deposited on it, giving the sensation of a crystallized and enchanted world.

The Omodeo is part of community sites of scenic and environmental interest. In fact, the history of this magical place is accompanied by natural beauty. The lake is surrounded by basalt plateaus, rugged mountains and captivating vegetation: holm oaks and Mediterranean scrub, as well as downy oaks, willows, poplars and elms. When exploring the waters in a canoe or kayak and the banks while trekking or taking relaxing walks, you will observe the flight of peregrine falcon and the jay, various species of ducks and herons, turtles and tortoises.