Originally the Doornenburg castle was a fortified manor built in the 9th century, under the name Villa Dorenburc. In the 13th century it was converted into a modest castle. Through the centuries the castle was expanded further into the current form. The front-castle was built in the 15th century. The front-castle contains sleeping quarters, a chapeland a farm, the last being a unique feature for a Dutch castle. It is one of the biggest and best preserved castles in the Netherlands.
Castle Doornenburg was occupied until the 19th century. After that it fell into neglect. In 1936 the Stichting tot Behoud van den Doornenburg was created, which had the castle restored from 1937 to 1941. In the end of the Second World War the castle was almost completely destroyed. It was long thought the Germans had blown it up, but it turned out that the castle had been hit by a British bombardment in March 1945. The castle was completely rebuilt from 1947 to 1968.
References: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.