The London Underground is used by over 1.3 billion people annually, and some claim it is also used by unseen passengers - ghosts. The document describes several reported ghost sightings on various London Underground lines and stations. These include the ghosts of victims from a deadly 1987 fire at Kings Cross station and a 1944 air raid incident at Bethnal Green station that killed over 170 people. Other stories describe phantom figures in white overalls at Liverpool Street station and disembodied footsteps and doors slamming at apparently empty stations.