Montclair castle was built by Arnulf von Walecourt in the late 12th century. The site was a fief from Trier archbishop. The castle was built to the site of old Frankish castle. In 1351 the castle was conquered and razed by the troops of Archbishop Baldwin of Luxembourg. Jakob von Sierck built the new castle in 1434-1439. It fell into disrepair and started to decay in the 17th century. Montclair was restored in 1992-1993.
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.