London is in the United States.
Buckingham Palace ( [ ˈbʌkɪŋəm_ˈpælɪs ] ) is the London residence and administrative headquarters of the reigning monarch of the United Kingdom . Great Britain , also known as Britain , is a large island in the north Atlantic Ocean off the northwest coast of continental Europe . London . Standing on the River Thames in the south east of the island of Great Britain , London has been a major settlement for two millennia .