The Desenzano Castle, erected in the Early Middle Ages, was most likely built on the foundations of a Roman fort. While the southern part of the castle was expanded it never became a military fortress, even if the structure was enlarged to house a garrison. The castle continued to primarily serve as a refuge for the local citizens. The castle housed the dwellings of private citizens who, in the event of danger, provided shelter to those who lived outside its walls.
Over the years, the castle gradually lost its function as a refuge, continuing to be inhabited by families, although its degradation, for most of the 19th century, continued to worsen.
In the castle, the Church of San Ambrogio was used as a private home. The plan of the castle is that of an irregular rectangle, with the tower that stands at the entrance, on the north side, to protect the drawbridge (that contains loopholes for chains). It is a massive tower with windows only at the top.
The remains of the ancient castle - of great historic interest and scenic charm – that can still be seen today include sections of curtain walls with crumbling battlements between the four corner towers, with the exception of the north-east corner that, until 1940, was used as an observatory .
The castle is open to the public. Visitors can walk to the side of the tower, go up two floors and enter the tower and climb up to the highest point (the observation deck), with windows offering an incomparable view of Lake Garda.
Under the battlements of the walls, the walkway up to the Torresin del Pontesello has been restored. Walk down the spiral staircase to catch a glimpse of the mouths of cannons.
A small arena below the castle is used for hosting historical re-enactments, parades and summer concerts.