The Freudenberg castle was one of the largest castles in region. The main castle dates from the first half of the 13th century and consists of a keep with a trapezoid floor plan. The curtain wall was 80m long and 60m wide and protected by a round tower in the southwest corner.
The castle was built by the Lords of Wildenberg. Later it was owned by several families and the imperial Austria. Because of a dispute over the legacy of the last Count of Toggenburg Freudenberg was besieged on May 26, 1437 by troops from Zurich. The castle was taken by the besiegers, plundered and set on fire.
Since 1985 the site has been owned by the municipality of Bad Ragaz and can be visited freely.
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.