The La Bâtiaz castle was built in 1260 and is the only remaining witness to the medieval era. It was an object of envy, and passed from the House of Savoie to the Sion bishops (and vice versa) many times. Dishes influenced by medieval flavours are served during the summer season.
There are panoramic view over the surrounding vineyards and Rhône Valley from the castle tower. The castle also hosts collection of medieval torture instruments inside. The château's medieval tavern, À la Part des Anges is now a highlight with its medieval menu.
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.