Corbera Castle is an impressive Muslim fortress, whose foundations lay on Roman remains. It has an irregular base, following the shape of the hill on which it rests. It was constructed in the 11th century to control the foothills of Murta and the coast. It is still possible to see the wall, the buttresses of the parade enclosure and the albarrana tower, which dates back to the Almohad period and it is one of the best-preserved towers in Europe. The complex was almost totally destroyed in 1521, during the Revolt of the Brotherhoods.
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.