London's Lost Subway - The Abandoned Mail Rail

Explore the fascinating history of London's Mail Rail, a secret automated underground railway system that operated beneath the city's streets for over 76 years. Discover how this hidden network of unmanned electric trains transported millions of letters through tunnels unknown to the public, designed to bypass Victorian-era traffic congestion and maintain efficient postal operations at industrial scale. Learn about the engineering marvel that functioned without drivers, its role during World War II bombings, and examine why this once-advanced infrastructure ultimately became obsolete in the face of modern logistics. Uncover the story of how cities historically solved transportation problems that we now take for granted, and understand the factors that led to the abandonment of this remarkable piece of forgotten London infrastructure.