Instituted in 1996, the Val Rosandra Regional Nature Reserve covers a surface area of about 746 hectares in the municipality of San Dorligo della Valle - Dolina, in the southeastern part of the Trieste province. It encloses a valley carved out by the Rosandra stream, and as the area is a meeting point between the mountain terrain and the coast, it is home to many animal species, some central European and others belonging to the Mediterranean ecosystem.