Slangenburg Castle was constructed in the Late Medieval period. In the 17th century the castle became the property of General Frederik Johan van Baer, also known as General Slangenburg, who rebuilt it for residential purposes.
The last private owners were a German family called Passmann, who are buried in a private cemetery next to the moat. After the World War II all German properties were confiscated by the Dutch government, who thus acquired the castle, which, with the surrounding terrain and the buildings within the outer moat, now forms part of the portfolio of the Rijksgebouwendienst ('Royal Buildings Service'), while the surrounding area falls under the care of the Dutch environmental agency, the Staatsbosbeheer.
At present the castle is used as a guesthouse by the nearby Benedictine monastery, St. Willibrord's Abbey, a newly built structure of the 1950s situated on a part of the castle's former estate. The original monastic community, from Oosterhout Abbey, was initially accommodated in the castle itself in the years immediately following the war.
The estate and the monastery chapel are open to the public. The estate, roughly trapezoid in shape, features a system of lanes which is centuries old.
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.