The Blitz was Nazi Germany's sustained aerial bombing ... (Getty Images) Firemen who fought the Second Great Fire of London recall fighting the fires until New Year 1941, in a film by J.B. Priestley.

By 1942, when the purpose-built tunnels were finished, the Blitz had ceased so they were never used for shelter. "It's real, it's emotional," says Mr Angus Murray, chief executive of The London ...