The Groß Raden Archaeological Open Air Museum is in a depression that borders directly onto the lake of Groß Radener See. On a peninsula in front of that lies its circular castle rampart, visible from afar, which has a diameter of 50 metres. From 1973 to 1980 extensive excavations were carried out here, led by Ewald Schuldt, during the course of which the remnants of a Slavic settlement dating to the 9th and 10th centuries was unearthed. The fort has been reconstructed based on the excavations and established as an archaeological open-air museum. It has been enhanced by finds from the Slavic castle of Behren-Lübchin.
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.