Borgsum

Borgsum is a municipality on the island of Föhr in the district of Nordfriesland, in Schleswig-Holstein, Germany.
The name means "Settlement at the castle". Said castle is the Lembecksburg, in fact a medieval ring wall with a diameter of 95 meters and a height of ten meters. According to old lore, it was constructed in the 9th century as a stronghold against the Vikings and is named after the knight Klaus Lembeck who had allegedly been residing there as a steward of king Valdemar IV of Denmark in the 14th century. After breaking his feudal oath, though, Lembeck is said to have been besieged by the king's host. Ít is disputed though whether Lembeck ever set foot on the island. Archaeological findings on Sylt island in the late 1970s suggest, however, that the Lembecksburg and similar facilities on Sylt date back to the days of the Roman Empire.

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