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Photograph credit: Arild Vågen
Vaxholm Fortress is a historic fortification on the island of Vaxholmen in the Stockholm archipelago just east of the Swedish town of Vaxholm. The first structure, a wooden blockhouse, was constructed by King Gustav I in 1548 as a defensive structure and customs post at this strategic site on the sea approach to Stockholm. It was replaced by a round stone tower during John III's reign. The present buildings date to 1833; their design was inspired by ideas on fortifications propounded by French engineers the marquis de Montalembert and Lazare Carnot. The fortress has been listed as a state monument since 1935 and now houses the Vaxholm Fortress Museum.