Lake Arvo is an artificial reservoir located between mounts Melillo and Cardoneto, part of the municipal territory of Aprigliano and San Giovanni in Fiore (Cosenza). The second largest lake in Calabria, after lake Cecita, it has a diameter of 8.7km, a perimeter of 24km, depth of 30m and holds approx. 70 million cubic metres of water. The straight shoreline to the south contrasts with the irregularity of the northern end and its floor is mostly sand and pebbles.
It was built as a hydroelectric reservoir between 1927 and 1931 by damming the rivers Arvo, Bufalo and Fiego. Unusually, the dam was built in clay and well-compacted earth. It is 280m long and 22m high and was, at the time of construction, the longest in Italy.
Surrounded by the highest of the Sila peaks, it overlooks several mountain residential centres including Lorica and Rovale to the north.