Monastery of San Pedro de las Dueñas was built in the late 10th century and beginning of the 11th century. It is one of the most representative churches of Mudejar Romanesque in its Pre-classical period, began in stone and finished in brick (1087 and 1110) and Basilical ground plan.
Over the presbytery of the chancel stands a brick tower, it is square with progressively decreasing sections.There is an interesting collection of capitals. The most remarkable of them is the one known as 'de las siete monjas' (the seven nuns capital) and the chancel shows an interesting Christ by Gregorio Fernández.
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.