The exact history of the Wolfenstein Castle is unclear. The archaeological excavations have dated the construction to the mid-12th century. The first written document dates from 1283 when Gottfried von Sulzbürg changed his name Wolfenstein and started the nobility. Hans von Wolfenstein died childless in 1462 and the castle was moved to the possession of Bohemian (Czech) king. Wolfstein lost its importance in the 16th century after been damaged in War of the Succession of Landshut in 1504. The castle was abandoned and fell into disrepair.
Today, the ruins of Wolfenstein are in good condition. It went through extensive excavations and renovations in the 1990s.
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.