Britain or Great Britain or the United Kingdom of Great Britain and Northern Ireland is a state located northwest of continental Europe, in the British Isles.
The territory includes the island of Great Britain, the northern part of the island of Ireland, and numerous small islands. Northern Ireland is part of the United Kingdom and has a land border with another country, Ireland. All other borders are water.
The United Kingdom is a constitutional monarchy with a parliamentary system of government.The monarch is Queen Elizabeth II, who has formally ruled since 1952, making her the head of state that rules the longest. The capital and largest city is London, a global urban and financial center with a population of 10.3 million people.
Other important cities are Birmingham, Manchester, Glasgow, Leeds and Liverpool.