Located in Sønderborg Castle, the museum teaches the history of South Jutland, starting in medieval times. It focusses on the wars of 1848-50 and 1864, World War I, the referendum and reunification in 1920. There are also spectacular cultural-historical collections from Sønderborg, Als and Sundeved. The Renaissance era basilica is particularly worth a visit. It houses the oldest functioning organ in Europe.
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