Mail Rail: London's Secret Underground Railway for the Post

In the early 1900s, London's streets were jammed with horses, carts and early motor vehicles, and the mail was getting stuck in traffic. In 1911, the Post Office came up with a plan to get it out of the way: build a railway underground, just for post. The plan called for a narrow-gauge electric railway 6.5 miles long, running from Paddington in the west to Whitechapel in the east, with stations beneath the main sorting offices along the way. World War I delayed construction, and material costs rose afterward, but work resumed in the 1920s. The tracks were only 2 feet apart, and the tunnels ran about 70 feet below the streets. The first section opened for training in February 1927. In early December 1927, the first parcels were carried between Mount Pleasant and Paddington, just in time for the Christmas rush, and the rest of the line opened over the following weeks. The Post Office Railway is described as the world's first electric railway with driverless trains. Small electric trains ran automatically between stations, while staff underground loaded and unloaded the mailbags. For decades, the railway ran up to 22 hours a day, through eight stations beneath sorting offices and near major rail terminals. At its peak, it carried about 4 million letters a day. In 1987, it was renamed Mail Rail. But the world changed around it. Sorting offices closed, and more mail moved by road and air. Royal Mail found that Mail Rail cost several times more than using road transport for the same work. By 2003, only three of its stations were still in use, and on May 31, 2003, the last mail train ran. The system was powered up one last time in 2005 so it could be filmed, then shut down. The tunnels didn't stay dark forever. On September 5, 2017, The Postal Museum opened a new attraction: about 1 kilometer of the original line beneath Mount Pleasant, with new passenger trains built to fit the tiny tunnels. Visitors now ride where London's mail once traveled.