7. Mont Saint Michel, France
Either than holding one of the most beautiful castles in the world, this UNESCO world Heritage site is also a walled city. The countless tourists that visit Mont Saint Michel enjoy walking behind the ancient walls that protected the island from enemies for centuries. England made repeated failed attempts to capture the island during the Hundred Years War. They were unable to breach the fortifications and two of their wrought iron bombards that were left behind after a siege in the 15th century are still visible near the outer defense wall