Plön Castle is a landmark, a tourist attraction and the headquarters of the Fielmann Academy in Plön.
The landmark of Plön, which can be seen from afar from all access routes by land and water, was built during the Thirty Years' War between 1633 and 1636. The Duke of Plön, Joachim Ernst, had a brick castle built on the site of the old, useless castle. The castle was given its white coat of paint in the 18th century under the Danish King Christian VIII.
At the turn of the century, Plön Castle was used to educate the sons of Emperor Wilhelm II and as a cadet school for the officer corps of the Prussian army. During the Nazi era, it served as the National Political Education Institute (NAPOLA).
After the state government sold Plön Castle to the non-profit Fielmann Academy in January 2002, the castle was completely renovated and reopened three years later after careful reconstruction in cooperation with the monument preservation authorities and involving local craftsmen. Since 2005, the Fielmann Academy has been training more than 6,000 opticians every year at Plön Castle as a public training center for German opticians.
The reconstructed chapel, the Knights' Hall and the ducal chambers can be visited on regular tours. The Knights' Hall is used for the classical concert series "Castle Concerts".