Oberalteich Abbey, dedicated to Saints Peter and Paul, was founded in c. 1100 by Count Frederick of Bogen, a lord protector of Regensburg cathedral. After a serious fire in 1245 the premises were re-constructed under abbots Heimo (1247 to 1252) and Purchard (1256 to 1260). Under abbot Friedrich II (1346 to 1358) the abbey was fortified. The church was extensively altered in the time of abbot Johann II Asperger (1438 to 1463). The medieval monastery complex was modernised by abbot Veit Höser (1604 to 1634), which was followed by a total baroque refurbishment from 1682-1721.
The abbey was dissolved in 1803 during the secularisation of Bavaria, and the monastery buildings were disposed of. Accommodation for the local priest and a servant were set up in part of them.
The abbey church of Saints Peter and Paul was rebuilt between 1622 and 1630 and is richly decorated. The baroque high altar dates from 1693. The church of the former abbey became the parish church in 1803. In 1847 the tombs and monuments were removed from the church and taken to Vilshofen where they were used for the construction of a dam.
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.