The waters around Slettnes have been known as a dangerous stretch of the shipping lane since ancient times. Both fishermen and the shipping community appealed for a lighthouse to be built here in the late 19th. century. The first lighthouse was erected between 1900 and 1905, and the lamp was lit on September 15th. 1905. In 1922, a fog horn was installed. During the 2nd. world war, the occupying German forces were in command. During their retreat in 1944, a complete destruction of the lighthouse was attempted. However, they did not manage to destroy the tower completely, and ten cast iron rings remained standing. Today, Slettnes is the only iron tower in Finnmark, as all other lighthouses were fully destroyed by the German forces and reerected in concrete after the war. In 1955, a radio beacon with a range of 50 nautical miles was installed, and in 1956 the lighthouse was connected to the local power supply network. In the after-war decades, up to four families lived here at the same time. In 1973, shifts were introduced and the staff’s families could settle elsewhere. Since 1998, Slettnes lighthouse has been protected by the cultural heritage act. In 2005, the lighthouse was automatized an de-manned.