The London Underground has always been key to the lives of Londoners, from when its stations and stairwells offered refuge from the barrage of the Blitz through to its unique ability across the years to transport people safely all around the capital. It has remained strong in the face of devastation, surviving horrors like the Moorgate Tube crash and the 7/7 bombings. An icon throughout the world, the Tube is as resilient as any Londoner, and is the thread that holds the capital together. These stunning photographs from the Mirrorpix archives present its changing face over time.