The next time you're waiting for the Tube in London, consider the secrets that lie beneath your feet – or right in front of your eyes. There are Roman remnants at Tower Hill, 1960s time capsules at Notting Hill Gate and beautiful-yet-abandoned station entrances, all with incredible stories worth knowing. Take a tour with us as we reveal the hidden secrets of London's Underground network, from Ice Age glaciers to its newest route, the Elizabeth Line.