Hisn Yakka is the name given to an old Muslim fortress and town, predecessors of the current city of Yecla. It was inhabited between the 11th and 13th centuries, as the town was abandoned after 1266 after the Mudejar revolt and the new Christian settlers settled on the opposite side of the mountain.
Hisn Yakka was built at the end of the 11th century in the Almoravid period, but it was not until the 12th century that the town or Madina appeared on the sunny side.
After the Christian conquest of the kingdom of Murcia, the Muslim population became a vassal of the King of Castile, which made the living conditions of the population more difficult, discontent that caused the Mudejar revolt. A large part of the Mudejar population had to leave the area at the end of this revolt, and it is likely that this was also the end of Yakka.
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.