Castalla Castle sits on a hill overlooking the valley and the town is around. Although its origins are Moorish, the current structure dates from medieval times. James I of Aragon took the castle from the Moors after the conquest of Biar and integrated it into the Kingdom of Valencia, under the Treaty of Almizra (1244), was in Castalla border with Castile. For this reason, started rebuilding the castle and was consecrated the first church in the place where the present chapel of the Blood.
The Torre Grossa tower was added in the 16th century in order to keep a lookout for pirate raids from the Mediterranean Sea.
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.