Secrets of Britain: Secrets of Underground London

SYNOPSIS

This series visits famous British buildings and institutions to reveal its past and present, meeting a wide range of experts and historians along the way. The first episode explores the secrets of underground London. On the surface, London is a buzzing, modern metropolis - but underneath lies secret, hidden worlds, all but forgotten by the millions of people above. The program uncovers 2000 years of subterranean history: a world of ancient caves and perfectly preserved Roman remains; mysterious rivers and gruesome plague pits; impenetrable vaults and top-secret bunkers.