Located on an island in the Schlei, a narrow inlet of the Baltic Sea, Schloss Gottorf is a historic castle estate that served as the House of Oldenburg's ancestral home. It lies just a couple of kilometers from the Old Town of Schleswig and boasts two of the state’s most significant museums.

The island was first settled as an estate in the 12th century as Bishop Occo of Schleswig's residence before being transferred to the Count of Holstein of the House of Schauenburg in 1340. It was later inherited by Christian I of Denmark, who was the first Danish monarch from the House of Oldenburg.

Schloss Gottorf was expanded throughout the years, particularly during the 16th century, when it became Christian I's primary residence, with the castle seen today built by the famous Swedish architect Nicodemus Tessin the Younger around the turn of the 18th century. It largely fell into disrepair under Frederick IV of Denmark's reign and was used as a barracks for both Danish and Prussian forces during the 19th century.

After being used as a displaced person camp during World War II, Schloss Gottorf was extensively renovated and restored in the post-war years. It is now owned by the State of Schleswig-Holstein and houses both the State Art and Cultural History Museum and the State Archaeological Museum. The State Art and Cultural History Museum boasts an outstanding collection of works dating from the high Middle Ages to contemporary art. At the same time, the State Archaeological Museum spans around 120,000 years of German history.