Plön Castle

Plön Castle (German: Plöner Schloss) in Plön is one of the largest castles in the north German state of Schleswig-Holstein and the only one located on a hill. The former Residenz of the Dukes of Schleswig-Holstein-Plön was built in the 17th century during the Thirty Years War and has had a colourful history in which it has, for example, been a school for military cadets and also a boarding school.

The castle ended the twentieth century as a possession of the state of Schleswig-Holstein, but they could not fund its renovation and so it had to be sold again. Since January 2002 it has belonged to the Fielmann Akademie Schloss Plön and, after extensive conversion, serves as a training and qualification centre for a branch of optometry. After being inaccessible to the general public for many years when it was a boarding school, its new owners have opened it to a limited extent to visitors.

The earliest Wendish defensive fortification called Plune dates to the 10th century and was located on the island of Olsborg in Lake Plön. It was destroyed in 1158. The rebuilding of the castle was carried out under Count Adolphus II of Holstein, and it served as a base during the colonization of the once-Slavic region. In 1173 the castle was moved to the Bischofsberg hill next to the small town of Plön - to the site of the present Plön Castle. In the 12th century Plön developed slowly into a market town and was given town rights in 1239. From 1290 to 1390 the hill castle was the seat of the Schauenburg line of Holstein-Plön and, after their extinction, was transferred to the Duke of Schleswig, Gerhard VI. Through the dukes of Schleswig, the small fortress was passed, four generations later, to the Danish royal family (Christian I was Duke of Schleswig and King of Denmark in personal union). During this period, however, Plön and its castle played no significant role in the country's history.

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