The total area of the United Kingdom is approximately 243,610 square kilometres (94,060 sq mi). The country occupies the major part of the British Isles[115] archipelago and includes the island of Great Britain, the northeastern one-sixth of the island of Ireland and some smaller surrounding islands. It lies between the North Atlantic Ocean and the North Sea with the south-east coast coming within 22 miles (35 km) of the coast of northern France, from which it is separated by the English Channel.[116] In 1993 10% of the UK was forested, 46% used for pastures and 25% cultivated for agriculture.[117] The Royal Greenwich Observatory in London is the defining point of the Prime Meridian.