River boats travel along the River Thames in London, allowing passengers to see landmarks like Big Ben, the London Eye, Tower Bridge, and The Monument. Big Ben is a large clock tower that houses a 13,500 kilo bell. The London Eye is a giant Ferris wheel that opened in 2000 and offers views across the city from the top of its slow-turning capsules. Tower Bridge opens to allow tall ships to pass through the River Thames before closing again. The Monument commemorates the Great Fire of London in 1666 and stands 61 meters high near where the fire started in a bakery shop early one Sunday morning.