The United Kingdom consists of four countries: England, Wales, Scotland, and Northern Ireland. London is the capital of the UK. It is a constitutional monarchy led by Queen Elizabeth II as head of state. Though the Queen reigns, she does not rule - the country is governed by an elected parliament and prime minister. Some of the UK's most famous places include universities in Oxford and Cambridge, Shakespeare's birthplace of Stratford-upon-Avon, and landmarks like Stonehenge and the Tower of London.