St. Olav's Cathedral is the cathedral of the Roman Catholic Diocese of Oslo. At the time of construction, this church, being built at Hammersborg, near the graveyard of Our Saviour, was located in the countryside outside the then city of Oslo. The work was funded by private donations and fundraising abroad, the most generous individual donor being Queen Josephine, who was a Catholic herself.
The first mass of the church was celebrated on August 24th, 1856, but as there was no Roman Catholic bishop in the country, the church was not consecrated until August 8th, 1896. When the Roman Catholic Diocese of Oslo was established in 1953, St. Olav's was chosen as the episcopal seat and was elevated to the rank of cathedral. It is the second Catholic cathedral in Oslo. The St. Olav's Cathedral was visited by Pope John Paul II when he visited the Scandinavian countries in 1989.
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.