In the North Atlantic Ocean

Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of 209,331 km² (80,823 sq mi), it is the largest of the British Isles, the largest European island, and the ninth-largest island in the world.^{[6][note 1]} In 2011, Great Britain had a population of about 61 million people, making it the world's third-most populous island after Java in Indonesia and Honshu in Japan.^[8][9] The island of Ireland is situated to the west of Great Britain, and together these islands, along with over 1,000 smaller surrounding islands, form the British Isles archipelago.^[10]

The island is dominated by a maritime climate with narrow temperature differences between seasons. England, Scotland, and Wales are mostly on the island of Great Britain, and the term "Great Britain" is often used to include the whole of England, Scotland and Wales including their component adjoining islands.^[11] Politically, Great Britain and Northern Ireland together constitute the United Kingdom.^[12]

A single Kingdom of Great Britain resulted from the union of the Kingdom of England (which had already comprised the present-day countries of England and Wales) and the Kingdom of Scotland by the 1707 Acts of Union. In 1801, Great Britain united with the neighbouring Kingdom of Ireland, forming the United Kingdom of Great Britain and Ireland, which was renamed the "United Kingdom of Great Britain and Northern Ireland" after the Irish Free State seceded in 1922.