Mühlbacher Klause (Chiusa di Rio Pusteria) castle was built by Sigmund, Duke of Tyrol, between 1458 and the 1480's. It replaced an older fort, built in the 13th century and which was situated about 600 meters west of the present location.
Both fortifications were built here to control the passage through the Pusteria valley which was the border between the counties of Gorizia and Tyrol.
In the 18th century an administration wing, once annexed to the residential building, was destroyed by a flood. Around 1871 the northeastern tower was partly destroyed.
The most recent wartime involvement of the castle dates from the so-called French War at the beginning of the 19th century, when Napoleon's troops were faced by the Tyrolese militia.
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.