The Natural Reserve of Tevere -Farfa is a lovely wilderness, rich in vegetation, reed beds and water birds. It was the first protected area to be created in Latium and has been recognised as a site of interest to the European Community and an area deserving special protection. It covers 700 hectares of the lower part of the Tiber Valley, in three different municipalities, preserving important birdlife and vegetation.

Its origin is tied to the morphology of the Tiber that in this part of its course is very slow flowing, forming loops and meanders and to the building of the hydroelectric dam in the years between 1953 and 1955. The slow flowing waters mingling with those flowing in from the Farfa Torrent have created Lake Nazzano, over the years, on its banks a unique riverin forest of willows, poplars, alders and a typical wet land habitat has sprung up. In appreciation of this the Italian WWF, the Municipality of Nazzano and ENEL, the electricity supply commission have created an oasis for the protection of its flora and fauna.

The most interesting and abundant of the fauna, even because it is very easy to spot, is its rich birdlife. The place offers refuge to nesting birds, migratory flocks and spices that choose to winter here.

The highest concentration occurs during the autumn migration, when birds from Northern Europe move to the Mediterranean Basin or to North Africa. In the reserve 187 spices of birds have been recorded, this is equivalent to a third of all birds recorded in Italy.

The reserve hosts numerous mammal spices, of which six are on the endangered spices list. There are also numerous reptile and amphibious spices; 22 of the 33 recorded in Latium. At the confluences of the Tiber and Farfa, an area within the reserve, 14 spices of fish have been recorded of which 8 indigenous and six of them endemic.