The oldest parts of the Reerslev Church, nave and the chancel, date back to the 12th century and are in the Romanesque style. In the 15th century, a chapel, a vestry and an extension of the nave to the west were added in the late-Gothic style. Cross vaults were also added during this period.
The cross vaults were decorated by the Isefjord school around 1450. After the Reformation, they were covered with limewash for centuries until they were uncovered and partly restored by Jacob Kornerup in 1873. They present pictures of Christ's birth, the Three Kings, children being killed under Herod's orders, the flight to Egypt and the arrival in Jerusalem on Palm Sunday. There are also scenes of the Last Supper, Jesus praying in Gethsemane, Pilot washing his hands, the Crucifixion and the Resurrection.
The church's altar with its panels from 1590 and the pulpit from 1609 are also of interest.
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.