Although the engineering contributions of Marc Brunel and his son Isambard Kingdom Brunel are commonly taken for granted, here they’re given their due. With the help of a shield system they invented, these pioneers executed the first tunnel to be built under a navigable river. London’s soft earth didn’t make it easy, though—it took from 1825 to 1843. This red brick building marked by a chimney was where steam engines pumped the seeping water out as diggers toiled. The tunnel, lined with arches and Doric capitals, was a commercial flop that deteriorated into a subterranean red-light district. It later found new purpose, however, as a part of the Overground Line, and it has gained new respect through this museum, which often creates special events to bring guests into the tunnel. Maximize immersion by combining it with a London Walks tour from Bermondsey Station to the museum door (current times are listed on the website; no reservations needed).