The Fortress of Verrua Savoia dates back to the 10th and 11th centuries. During the wars the fortress was destroyed and rebuilt several times. Currently, only the Dungeon and the Ponte del Soccorso remained of the fortress. Prior to the French siege of 1704 the defence consisted of an enclosure wall and 4 bastions. The main part of the fortress consisted of the keep, barracks and of a well.
References:Towering 52 meters above the sea, Bengtskär lighthouse is the tallest one in Scandinavia. The building started in in 1905 after the shipwreck of S/S Helsingfors and was completed in 1906. The lighthouse was designed by architect Florentin Granholm. On December a special petrol lantern, designed and built in Paris, was brought to Bengtskär and installed atop the tower.
German fleet bombarded Bengstkär in the First World War in 1914. Since the Gulf of Finland was heavily mined, it was not until 1919 that the surrounding seas were declared safe for shipping, that the light was lit again.
After the war the military value of Bengtskär increased as part of the defence system of independent Finland. In Second World War (1941) Soviet Union made a suprise attack to island. After a bloody battle, the small Finnish garrison emerged victorious. Intermittent repairs to the facility continued during the post-war period.