From 1928 Corenno Plinio became part of the Municipality of Dervio.
At the top of the promontory of the hamlet of Corenno rises the Castle of the ancient Andriani family, now extinct. It was built in the fourteenth century. on the remains of an ancient fortress, as a defensive enclosure, and has two towers, one square to the north and one to sail, with the entrance facing the Corenno Square.
The castle is a monumental complex set on Roman foundations, as can be inferred from the base of some walls, and has an irregular plan basically square-shaped. The panoramic position of the settlement suggests that in this Roman period there was one of the signaling and guard towers that allowed to transmit important news from the provinces of the Empire to Rome, with signs of smoke during the day and with fires overnight. The castle, composed of an irregular-shaped city wall, crowned with merlons that protected the walk, can be dated between 1360 and 1370 and is a typical example of a castle-enclosure, that is a fortification built as a refuge for the population in case of attacks.
The material used for the construction follows the type of the opus gallicus, with the use of material from rock excavated on the spot or recovered on the shore of the lake. The stone is generally small. On the front of the door stands the emblem of the Andreani. It has two towers, one of the so-called sailing type (ie open inside) overlooking the only opening facing the village, to the southwest, and the other square and located in the north-east corner, probably added to the walls in the second half of the fourteenth century; it constituted the nucleus through which the town of Corenno developed with the characteristic streets carved into the rock.
It can be said that the castle is the last bastion of a fully fortified country: those who wanted to conquer Corenno from the lake (the only access route in ancient times) was facing a village built on a rocky spur, with steep streets and narrow, sturdy doors and connected by long stairways carved into the rock, with the houses superimposed on each other without windows. A castle enclosure where the population took refuge waiting for the fury of the enemy to take off.