The encyclopedia · Strategy & Leadership · Operational decision · 1927-2003
Mail Rail moved London's post on driverless trains under the streets
Royal Mail built a 6.5-mile driverless underground railway so letters crossed congested London in minutes.
Royal Mail
the move
By the 1920s London's mail moved by van between sorting offices and railway stations, and every van sat in the same streets as taxis, carts and buses. The cost and unpredictability of moving letters across the capital kept growing as the city did, and the surface offered no way out.
The Post Office chose to go under it. It built the Post Office (London) Underground Railway — Mail Rail — a 6.5-mile loop of narrow tunnels beneath the capital, and ran small, driverless electric trains on it. A train left Paddington Station every seven minutes, carrying letters east to Whitechapel and stopping at the main sorting offices along the way. Traffic was not avoided; it was bypassed entirely.
The line opened with parcel traffic in December 1927, in time for that year's Christmas pressure, and the trains ran unattended in tunnels only two feet wider than their small carriages in places. Because the system was automated it could run on a relentless schedule, and all day and night the same quiet circuit carried the post that had previously depended on the streets.
Mail Rail carried letters and parcels under London for 76 years until it was abandoned in 2003, replaced by road and by the changes in how mail was sorted. Its tunnels and platforms were preserved and later opened to the public as the Postal Museum's Mail Rail attraction in 2017.
why it works
- Surface congestion made the cross-town mail leg slow and unpredictable
- A dedicated tunnel bypassed the shared streets rather than competing for them
- Driverless electric trains removed the cost and limit of crewed vehicles
- A fixed loop with trains every seven minutes ran at any hour
what transfers
When the problem is the shared surface everyone else is using, build your own sub-surface lane and the fixed cost beats a never-ending expense in drivers and delays.
what came after
Mail Rail ran from 1927 to 2003, carrying letters and parcels between London's sorting offices for 76 years, before motor transport took over. Its surviving tunnels became the Mail Rail attraction at the Postal Museum in 2017, and the idea of a dedicated, automated sub-surface freight lane resurfaced later in proposals for underground parcel delivery in other cities.
references
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