Castello di Rossino, Medieval castle in Calolziocorte, Italy.

Castello di Rossino is a medieval castle in the Rossino hamlet of Calolziocorte, in Valle San Martino. It consists of a keep inside a walled courtyard, with a 13th-century window, and a main building called "la dogana", which retains its original structure with an entrance portal and two windows used to collect tolls. The walls of the facade rooms date to the 19th century, while other sections are older and built with reused Roman-era materials.

A Roman military post on the Bergomum-Comum road preceded the castle; the first written record dates from 1281, when notary Viviano Gatti documented the seizure of goods belonging to Giovanni Salvioni de castro Russino. In the 14th century the Benaglio family included it in their defensive system against the Suardi, and in the second half of that century it passed to the allied Rota family of Carenno.

The castle's name comes from the Rossino hamlet, and its role as a commercial hub for wool, wine, chestnuts, grain and fish lasted until the 17th century. The Rota family ran this trade from the castle, which also hosted land sales for the whole valley.

The castle stands in the Rossino frazione of Calolziocorte, on the height above the road that once linked Bergamo and Como. The main building, called "la dogana", keeps its entrance portal and two windows where merchants paid the duty between the Duchy of Milan and the Republic of Venice. The north-west corner tower was lowered and absorbed into the curtain wall.

Popular tradition holds that tunnels ran from the castle to piazza Regazzoni, about 0.5 km away, and to the castle of Somasca, 1.5 km off. Twentieth-century finds confirmed masonry passages tall enough for a man to walk upright, fitted with deep hidden wells as traps; roadworks, sewers and later buildings have since broken them into fragments.