Sudbury has lent its mining heritage to two major tourist attractions: Science North, which is an interactive science museum built atop an ancient earthquake fault on the shore of Lake Ramsey, and Dynamic Earth, an earth sciences exhibition which is also home to the Big Nickel, one of Sudbury's most famous landmarks drawing more than 210,000 visitors anually. Another city landmark, the Inco Superstack, is the tallest freestanding chimney in the Western hemisphere. As well, the Creighton Mine site in Sudbury is the site of the Sudbury Neutrino Observatory, the lowest background radiation particle detector in the world.