On Anglesey's top right corner is the headland known as Point Lynas. At its tip is Point Lynas lighthouse, which is unusual because the light room is almost at ground level. Having said that, its elevated position on the headland given the light a range of 20 nautical miles. The lighthouse was automated in 1989, and has an automatic fog warning system which comes into operation if visibility falls below 2.5 miles. The lighthouse was built in 1835 by the Mersey Docks and Harbour Board to facilitate the passage of shipping into Liverpool, and responsibility for its operation passed to Trinity House in 1973. The lighthouse, telegraph station and accommodation blocks are Grade 2 listed structures.