A closer look
Marc Brunel's Thames Tunnel was an engineering marvel, the first successful subterranean pathway built beneath a navigable river. But by the time it opened in 1843, the company was entirely out of money to build the access ramps for cargo carts. To recoup costs, they opened it to foot traffic, instantly spawning a bizarre underground tourism craze. Two million people a year paid to walk through a damp, sewage-scented tube filled with sword swallowers, fire eaters, and cheap souvenir stalls.
