The United Kingdom of Great Britain and Northern Ireland, or UK, is in Western Europe. It comprises the island of Great Britain (England, Scotland and Wales) and the northeastern one-sixth of the island of Ireland (Northern Ireland), together with many smaller islands. The mainland areas lie between latitudes 49°N and 59°N (the Shetland Islands reach to nearly 61°N), and longitudes 8°W to 2°E. The Royal Greenwich Observatory, near London, is the defining point of the Prime Meridian. The United Kingdom has a total area of approximately 245,000 km².

The United Kingdom occupies a substantial part
of the British Isles.

The UK lies between the North Atlantic Ocean and the North Sea, and comes within 35 km (22 miles) of the northwest coast of France, from which it is separated by the English Channel. Northern Ireland shares a 360 km international land boundary with the Republic of Ireland. The Channel Tunnel ("Chunnel"), bored beneath the English Channel, now links the UK with France.