De Trompenburgh is a 17th-century manor house designed by Daniel Stalpaert and built for Admiral Maarten Tromp, one of the naval heroes of the Dutch Republic. The house is almost entirely surrounded by water and was built to resemble a ship, even with decks and railings.
Before the current house was built another buitenplaats had been built by Andries Bicker in 1636. The original house dates back to 1654. Through inheritance the house came into the possession of the widow of Van Hellemont Raephorst who remarried on January 25, 1667 with Admiral Cornelis Tromp. The couple redecorated the estate considerably, but the house and their improvements were treasure looted and burned by the French during the rampjaar 1672. It was rebuilt in 1675-1684 by Maarten Tromp's son, Admiral Cornelis Tromp, who called it Syllisburg, after one of his titles. Around 1720 Jacob Roeters came into possession of the estate and he renamed it Trompenburg and had a gilded plaque with an ode by Gerard Brandt in memory of Tromp installed over the entrance in 1725.
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.