The modern search for the "Mary Rose" was initiated by the Southsea branch of the British Sub-Aqua Club in 1965 as part of a project to locate shipwrecks in the Solent. The project was under the leadership of historian, journalist and amateur diver Alexander McKee. Another group led by Lieutenant-Commander Alan Bax of the Royal Navy, sponsored by the Committee for Nautical Archaeology in London, also formed a search team. Initially the two teams had differing views on where to find the wreck, but eventually joined forces. In February 1966 a chart from 1841 was found that marked the positions of the "Mary Rose" and several other wrecks. The charted position coincided with a trench (one of the scour pits) that had already been located by McKee's team, and a definite location was finally established at a position 3 km (1.9 mi) south of the entrance to Portsmouth Harbour () in water with a depth of (36 feet) at low tide. Diving on the site began in 1966 and a sonar scan by Harold Edgerton in 1967–68 revealed some type of buried feature. In 1970 a loose timber was located and on 1971, the first structural details of the buried hull were identified after they were partially uncovered by winter storms.