The 'Ravelijn op den Zoom' (ravelin) is the last remnant of the fortifications designed by Menno van Coehoorn. The ravelin consists of a island with earthen and stone walls, surrounded by a wide moat. The ravelin is one of the few remaining parts of the extensive fortification system around the city. The fortress was so ingeniously designed that it was assumed that it could not be taken and therefore got the nickname 'La Pucelle' (Virgin). In 1747 the city nevertheless became occupied by French troops.
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.