The Breno castle rises on a hill overlooking the town: the building was erected in the 12th century, then turned into a military stronghold at the time of the Venetian Republic (1400-1500) and finally, after being abandoned in 1598, it was reused as a stone quarry.
The castle however rises on a much more ancient site: probably the place where in the 10th-9th century BCE a prehistoric community settled.
You can reach the castle with a short walk (about 15 minutes) from the centre of Breno: the perimeter is closed by a battlemented boundary wall and by two towers. Inside you can admire the remains of the St. Michele church, of Longobard origin, then enlarged in the Romanesque period. The other buildings, the only remains of which are mostly the outside walls and the cellars with barrel vaults, were added during the Venetian reign.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.