The Haichenbach hilltop castle is located at an altitude of 450 meters above sea level on the ridge that forms the so-called Schlögener Schlinge on the Danube.
The first documented mention of Haichenbach dates back to 1160. At that time, Otto and Wernher de Eichenbach are mentioned as representatives of the ministerial noble family that derived its name from the castle. In 1273, the castle must have burned down for unknown reasons, as Rueger von Haichenbach documented in Schlägl in 1274 that he allowed the use of his forests in exchange for accommodation in the monastery hospital, during the time Haichenbach was being rebuilt.
After 1529 Haichenbach Castle was abandoned. Since 1984, restoration measures have been undertaken by the Working Committee for Homeland Care Hofkirchen; the castle ruins can now be safely visited.
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.