London in One Day Sightseeing Tour. See London in one day on a full-day sightseeing tour of the city, led by an expert local guide! Hear the history of top London attractions like Westminster Abbey, Big Ben and St Paul’s Cathedral while traveling around the West End and City of London. After the sightseeing tour, watch the Changing of the Guard Ceremony at Buckingham Palace and tour the Tower of London with a Beefeater. Book now and Save 10%: London in One Day Sightseeing Tour.