where does the english channel end and the north sea begin
English Channel The IHO defines the southwestern limit of the North Sea as "a line joining the Walde Lighthouse (France, 1°55'E) and Leathercoat Point (England, 51°10'N)".[3] The Walde Lighthouse is 6 km east of Calais (50°59′06″N 1°55′00″E﻿ / ﻿50.98500°N 1.91667°E﻿ / 50.98500; 1.91667), and Leathercoat Point is at the north end of St Margaret's Bay, Kent (51°10′00″N 1°24′00″E﻿ / ﻿51.16667°N 1.40000°E﻿ / 51.16667; 1.40000).