What would happen if the London Underground ceased to exist? When Alex Day visited Wales to find the oldest passenger train in existence, he discovered it wasn't there. Faced with the idea that this could happen to the tube, he set off to visit every station - all 270 of them - to see what stories they had to share and preserve them forever. Funny, fascinating and touching, this is a tale of one man's obsession, adventure and the human stories that are only a train ride away.