The Monte Serra di Sotto Nature Reserve is located in the Municipality of Buti, on the south-east side of Monte Pisano. The protected area is crossed by a network of dirt roads and paths that connects the towns and villages of the area.
The reserve's environment is characterized by the presence of species of high naturalistic interest. Among the reptiles that can be found are the fire salamander, ringed snake, aesculapian snake, and the whip snake. Species of bird include the woodlark, the blue rock thrush and kestrels, while the most interesting mammals are the dormice and hazel mice. The reserve is also inhabited by porcupines, land voles and dwarf bats.
The landscape is mainly made up of maritime pine forests, evergreen sclerophyllous and conifer woods, and planted chestnut and olive groves.