Osterburg

The castle occupies a triangular rock terrace that drops steeply to the south into the Pielach gorge, a setting that concentrated defensive works toward the higher ground on the northern side. Construction shows medieval masonry techniques, with rubble walls in many places; the building phases include Romanesque and later Gothic work, and several parts bear traces of alterations from different centuries.

A Romanesque rear defensive tower dates to the thirteenth century. This round tower measures roughly ten metres across and has walls up to two metres thick. A stairway ran within the tower wall to link the floors, and the entrance was set high on the south face. Openings in the tower wall are limited to a few square light or shooting slits, reflecting its defensive purpose.

Immediately north of the tower the site is protected by a section of ring wall and a fore-ditch. Above this line of defense stands a medieval fortified large farmstead that acted as an added screen for the castle. The area that once formed a roomy outer court now carries a road running between the tower and the main residential block.

The main residential building, or palas, dates from the early fifteenth century and presents three storeys arranged in three wings. Parts of its exterior show exposed rubble masonry, and seven stone heraldic shields fixed to the wall since the mid seventeenth century are still visible. A clear masonry seam with large corner stones on the north side marks the later insertion of a set-back west wing. Projecting double dismounting bays supported on corbels are a notable feature, and the interior contained a large hall in the west wing and another large hall in the central range. Some Gothic reinforced shoulder-arch doorways survive, and the uppermost floor long served as a grain store.

The eastern cross-wing once housed a two-storey chapel that was later divided by an inserted wooden floor. On the chapel’s upper level there was a late Gothic ribbed vault and a pointed-arched tracery window; fragments of that vault remain in place. The eastern gatehouse and the bridge that formerly spanned the ditch are recorded as having been removed in the later history of the site. Materials from parts of the medieval fortifications and residential buildings were taken in 1766 for work at Schloss Mitterau. The remaining ruin passed from the Montecuccoli family in 1983, and beginning in 1985 parts of the site were made habitable again and received partial renewal.