The area of sea around the islands of Orkney below mean high water springs enclosed by a line extending from Tor Ness on the Island of Hoy at 58°47'North latitude 3°17.5'West longitude; then due south to a point at 58°45'North latitude 3°17.5'West longitude; then due east to a point on the mainland of South Ronaldsay at 58°45'North latitude 3°West longitude; then north along the shoreline South Ronaldsay to 58°50'North latitude 3°West longitude; then due north to a point on the Mainland at 58°57'North latitude 3°West longitude; then west and north along the Mainland shoreline to Breck Ness at 58°58'North latitude 3°21'West longitude; then south and west to the Kame of Hoy on Hoy at 58°55.5'North latitude 3°24'West longitude; then east, south and west along the shoreline of Hoy to the point of beginning.