Gnandstein castle was built in the Romanesque style in the 13th century, probably only with a rectangular groundplan and a residential tower. Parts of the present building still date from this early period. The external walls were extended several times.
During the Thirty Years' War the castle was attacked by Swedish troops and partly destroyed. Shortly before the end of the war the south wing burned down after being struck by lightning.
The well house is more than 33 meters high, giving the visitor a broader view of the region. It was used as a watch tower. Guided tours are available.
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.