The ruins of Castello De Piro, also known as Castello Grumello, overlooks the valley from a rocky hill. The castle, made up of two linked buildings, with a huge square tower in the Eastern one, is a rare example of Twin Castle. It was built by the De Piro family at the beginning of the Fourteenth century.

The Grisons - the new rulers of Valtellina - decided to have it dismantled in 1526 after the fall of the Ducato Sforzesco. Close to the Contrada Cà Bongiasca ( m. 923 ) there are the remains of the Mancapane castle, built towards the end of the 13th century: a tower  and a fortified enclosure that had watchkeeping,  warning and defensive functions.