London is the capital city of England located on the River Thames. Some of its most famous landmarks include Big Ben, the London Eye Ferris wheel, the Tower of London historic castle, Westminster Palace where Parliament meets, Buckingham Palace residence of the monarch, and Trafalgar Square with Nelson's Column at its center. Other notable places include Oxford University the oldest in the English-speaking world, the National Gallery art museum, British Museum housing artifacts from around the world, and Royal Opera House opera venue in Covent Garden.