The Achi monastery is a single-nave hall church, built of hewn stone. Constructed at the end of the 13th century or in the early 14th, it was later reroofed, renovated and surrounded by a defensive wall. The whole interior is frescoed. Some murals, stylistically dated to the late 13th century and betraying affinities with the Palaeologan art, are iconographic rarities, such as those depicting the life of Saint George.
The Achi monastery was favored by the Princes of Guria, especially Simon I Gurieli and Kaikhosro I Gurieli in the 17th century. Both made significant donations to the church and Kaikhosro made it a metochion of the bishopric see of Shemokmedi. The abbotship of Achi was then hereditary in the Salukvadze-Taqaishvili family. The church housed a gilded silver cross with a Georgian inscription mentioning the queen Tamar, which was discovered by Ekvtime Taqaishvili. The item was preserved in the Salukvadze family during the Soviet period and returned to the Achi church in 2015.
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.