Göksholm is the oldest privately-owned building in Sweden that has been continuously inhabited.
In the middle ages Göksholm was just a fortified castle with a large tower. Its oldest existent parts have been dated to the 13th century. It was built (rebuilt and enlarged) during the Middle Ages through six different stages.
After a fire at the end of the 16th century, the building was modernized according to that period's style, getting a more regular plan, bigger windows and details in the Dutch renaissance style. Despite the thorough renovation, the medieval base structure remains. A painted inner ceiling from the time of this renaissance renovation exists with 121 cassettes which is remarkably well preserved today.
Under the 17th century owners, Baron Knut Kurck and Baron Fleming, the castle was encrusted with portals, and circle-patterned outer buildings. Lars Gustaf Tersmeden had the ceiling renovated in 1801. This was the last big change in its structure. Some facade details were changed in the 1950s.
Historically Göksholm is famous for the popular uprising's leader Engelbrekt Engelbrektsson, the leader of the government, having been murdered on its lands in 1436 by Måns Bengtsson, the son and heir of the then owner of the castle.
Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.