Why Tower Bridge Has a Walkway Nobody's Allowed to Use

Tower Bridge has two high-level walkways suspended forty-two metres above the Thames. They were built so pedestrians could cross even when the bascules opened for ships. Within sixteen years, the City of London sealed them shut because they had become a notorious haunt for sex workers and pickpockets. They stayed closed for seventy-two years. When they finally reopened, it was not as a crossing but as a paid exhibition with a glass floor. The walkways that nobody wanted to use became the thing everyone pays to stand on. This is the full story of how that happened.