http://www.aquatrek.co.uk/page21.html states: "Fidra is a beautiful island which was the inspiration for Robert Louis Stevenson's Kidnapped. Fidra light was the first in the Northern Lighthouse Service to be fully automatic in 1970. This light produced 460,000 candlepower which, even today, can be seen for over 16 miles. In 1971 the keepers were withdrawn from the island" . Admiralty Pilot NP54 describes the light as a white brick tower, 17m in height (58:04N, 2:47W).