“One of our very first explores took us to Cann Tunnel , a small partially flooded tunnel”
History of Cann Tunnel Plymouth
Cann Tunnel, also known as Leigham Tunnel by some local folk, was part of the Plymouth & Dartmoor Railway section between Crabtree & Roborough.
It was built in the 1820’s, by sinking a shaft which was then worked outwards. It was one of the first railway tunnels in England, & certainly the first in Plymouth.
The railway was the brainchild of Sir Thomas Tyrwhitt, who was also responsible for the earlier construction of Princetown & Dartmoor Prison, & its purpose was to carry granite from the Dartmoor quarries, peat & local produce from farms into Plymouth.
It was known as “The Dartmoor Gauge” due to its unusual dimensions being 4′ 6″ & wagons were horse-drawn, not by a locomotive. All of the tracks were removed in 1916, bar the section between Crabtree & Sutton Harbour in Plymouth, which was retained as part of the Lee Moor Tramway.
The tunnel itself is 620 yards in length & was adapted during WW2 as a deep shelter for the workers of Devonport Dockyard complete with a bus stop outside one entrance to transport workers into the dockyard, also containing bays for an underground hospital, should the Blitz on Plymouth get so bad.
This would have accommodated up to 3000 people. After the war, it was used by the Royal Navy for depth charges. In the 1950’s it was noted as part of a Central Register of Underground Accommodation.