The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a sovereign state located off the north-western coast of continental Europe. The country includes the island of Great Britain, the north-eastern part of the island of Ireland, and many smaller islands. Northern Ireland is the only part of the UK that shares a land border with another sovereign state—the Republic of Ireland. Apart from this land border the UK is surrounded by the Atlantic Ocean, the North Sea, the English Channel and the Irish Sea.