Sønderborg Castle

Sønderborg Castle is located in the town of Sønderborg, Denmark on the island of Als in South Jutland. It houses a museum focusing on the history and culture of the area. The castle is located in the middle of the town, in a park setting overlooking Als Fjord. The museum is open year-round.Sønderborg Castle began probably as a fortified tower constructed by Valdemar the Great in 1158, built on an islet in Als Strait that later was connected to the island of Als. As it lies to the south of the isle of Als, it was named Sønderborg, literally "southern fortress" . The castle was built to provide protection against attacks by the Wends and was part of a larger system of fortifications. Over the centuries, the castle has gradually been enlarged and rebuilt.

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