The retired Käsmu lighthouse is situated on the North Coast of Estonia in Käsmu bay. The lighthouse provided safe entry to the Käsmu bay with its green, white and red sector lights where it was possible to get storm shelter near the lighthouse. Käsmu bay was for centuries the best harbour of refuge on the Tallinn-Narva ship route. The construction was initiated by the board of Käsmu Maritime School.
Resembling a wooden pavilion, the 6m high white lighthouse started working in 1892. It was equipped with one-wick kerosene lamp and 5th Class dioptric apparatus which was visible for 6 nautical miles. The windows of the lantern room were divided with coloured glass so that they would emit green, white and red light. By 1922 the improved lighting was visible for 13 nautical miles. The lighthouse was in operation until 1993, after which it was used as a day- mark until 2004 when it was excluded from the list of navigational aids. Käsmu lighthouse is listed as an architectural monument.