Raschpëtzer is an artifical aqueduct (qanat) from Roman times, consisting of about 35 wells dug into the rock and linked together by a 600 m main passage and a net of secondary passages, designed to capture the underground water and take it to Roman villas.
Raschpëtzer is a particularly well preserved example of a qanat and is probably the most extensive system of its kind north of the Alps. It has been under systematic excavation for the past 40 years. It was built during the Gallo-Roman period, probably around the year 150 and functioned for about 120 years thereafter.
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.