The origins of Randeck Castle are unknown, but in the tenth century Duke Arnulf may have built built the first medieval fortress on the hill in order to protect the land against the raids of the Hungarians.
Baron von Rotteneck is said to have built the castle in the 11th century. In the 13th century the Counts of Abensberg took possession of the castle. The owner Jack von Abensberg was known as robber baron and the city of Nuremberg waged war against him. In 1446 his castles were demolished and burnt down. Niclas, the last Count of Abensberg, was killed in 1485 in a feud with a neighbouring family.
The castle was attacked by Swedish army during the Thirty Years´ War. Both castle and convent were destroyed. In 1838 a large part of the castle just collapsed after heavy rainfalls.
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.