Blankenstein Castle was built originally in 1227-1243 by Adolf I, Count of Mark. It was further developed over the course of 200 years by the Counts of the Mark. By 1425, Blankenstein was one of the most important castles in the county. In 1614, shortly before the Thirty Years' War, it was occupied by Spanish troops. From 1637, the castle fell into disrepair so that, in September 1662, Frederick William, Elector of Brandenburg ordered its demolition. Only the tower and parts of the curtain wall remained.
In 1860, the owner of the ruin, the employer, Gustav vom Stein, began to rebuild the castle and established a factory there. The property has belonged to the city of Bochum since 1922, but the town is looking for an alternative due to the costs. From 1957 to 1959, most of the buildings of the 19th century were pulled down, but some still remain.
The tower can still be visited and offers a good view over Bochum and the Kemnader Lake.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.