Bishop Rock Lighthouse, 19th-century lighthouse, Scilly Islands, Cornwall. The 19th-century civil-engineering landmark takes perhaps the worst buffeting from heavy seas of any lighthouse in the world. The first tower, begun in 1847, was swept away before the lantern could be installed. The present tower, of interlocking granite blocks with a solid drum base, was completed in 1858. It was subsequently reinforced by iron tie bars in the inner walls and a granite encasement of the outer wall. The structure was improved and its elevation was increased by Sir James N. Douglass in 1883–87. The lantern is 146 feet above high-tide level.