Erosion of the rock on which the original fog signal (built in 1899) stood, made it necessary to abandon it and to establish another fog signal nearer the lighthouse. A third fog signal was established in 1952, but this was discontinued in 1987.

James Smith of Inverness was the contractor responsible for the building of Dunnet Head.

All the new lighthouses, beginning with Little Ross in 1843, were lighted on the dioptric system the latter being a combination of lenses with reflectors. Dunnet Head was changed to a dioptric lens in 1852.

The Queen Mother had visited the lighthouse on several occasions, the last being on 8 October 1979 when Mr Malcolm, Principal Lightkeeper, gave a conducted tour of the station. The Queen Mother later had tea with Mr Malcolm and his wife and met the other lightkeepers and their families residing at the station.