Enjoy the highlights of London from a double-decker bus en route to Europe's tallest building, the Shard. you'll see Westminster Abbey, the London Eye, Big Ben, the Houses of Parliament and the Tower of London, then take a short cruise on the Thames River. With a stop at Buckingham Palace for the Changing of the Guard ceremony, and fast-track tickets to The View from The Shard, you'll cover many of London's top sights on this 5-hour tour with an expert guide.