London is the capital of England and the United Kingdom.Located on River Thames ,London is a leading global city with strengths in arts ,commerce ,entertainment ,fashion ,finance ,healthcare ,media ,professional services ,research and development ,tourism and transport.London is a world cultural capital and it has the third most international visitors in the world and London Heathrow is the word's busiest airport by number of international passengers.London has a diverse range of people and cultures ,having an official population of 7,825,200.London contains four World Heritage Sites:the Tower of London ,Kew Gardens ,the site comprising the Palace of Westminster ,Westminster Abbey ,St.Margaret's Church.It also has the historic settlement Greenwich in which the Royal Observatory marks the Prime Meridian.The London Underground is the oldest underground railway network in the world and the second most extensive.This one was very helpful during the Second World War ,because lot of people could save their lifes refuging there.
