The former castle of Collemontanino, of which only a few remains today, such as the large rectangular watchtower and ruins of the keep, dominated the hills over Valdera and played an important strategic role. According to legend, the castle is said to have been the home of Countess Matilda of Canossa, who discovered the beneficial waters of Casciana thanks to her sick blackbird.
The village was in fact divided into two parts: the castle in the highest part of the village and the hamlet with the small church square, old houses, small streets and walls. At the top of the slope, one can enjoy the panorama of the surrounding countryside. The parish church of San Lorenzo has a bare interior with a pietra serena altar and baptismal font. Mentioned as early as 1089, it underwent renovations over the centuries until the final restoration in the 1970s that determined its current appearance.
Nearby is the ancient Church of San Martino in Colle (8th century), a Romanesque structure with Etruscan influences, as shown by the funerary cippus used as a stoup. Leaning against the altar is a Roman stele, not yet deciphered.
The village is located next to a wooded area (called Poggio alla Farnia) where a complex of wind turbines has been installed for energy production.