The name obviously stems from the morphology of the territory and from the presence of hermits who had taken over a number of caves throughout the Valnerina.

The town of Grotti, in the municipality of Sant`Anatolia Narco, consists of two distinct parts: the first in which the remains of a tower and walls can be found; the second in a higher position where the church of the Addolorata stands.

The buildings are few and badly preserved with the intrusion of recent buildings. In the mediaeval statutes of the castles of the Valnerina a special chapter was dedicated to the Forestanza. There was a high tax for foreigners who asked for residence.

Grotti was one of the places that most discouraged the settlement of new families, perhaps  because the difficult layout of the castle, partly clinging to the rock, did not allow any more building to be done, but also because manufacturing resources were insufficient.