Wednesday 12 December 2012

Devonport Dockyard Deep Air Raid Shelter / Cann Tunnel

Site visits from 2006-2010

When I first came across photographs of this tunnel on Cyberheritage back in 2006, I knew I had to visit & see it with my own eyes, although it took months for me to actually find the point of access & I never actually got to walk the full length until early 2009. Many locals living within the vincinity hadn't even heard of it but they along with thousands of Plymouth people drive above it everyday, driving to & from work or doing their shopping at the large supermarket nearby. Just exactly why one of the world's (yes world!) oldest railway tunnels is not more cared for baffles me. Thankfully it still remains without threat of demolition after being resealed in 2010 as a home for bats & wildlife to thrive within.

The sealed north portal of Cann Tunnel

Built in the 1820's & part of the Plymouth & Dartmoor Railway, carriages were horse drawn & it was named "The Dartmoor Gauge" due to it's unusal size being 4'6". The tunnel is a staggering 620 yards in length & was converted during World War II to a deep air raid shelter & underground hospital for the workers of Devonport Dockyard had it taken more bombing from the Luftwaffe. From 1944, it was then used as Naval storage for depth charges. In the 1950's it was noted in the Central Register of Underground Accomodation by the government as a possible deep shelter in the event of a nuclear war. Thankfully this was never used for such a purpose.

To think though, that this would have accommodated upto 3,000 & possibly more, it begs belief & I could only imagine rows of triple bunks alongside one length of the lined corridors where horses once dragged their carts. In an area void of housing at the time, it would have provided the ideal safe haven on the outskirts of the city & much needed relief for workers to rest inbetween bombing raids but little history has been available as to it's actual attendance during raids until now.

Inside the south portal - It's minus 4 outside & a warm mist inside the tunnel

My first visit to Cann Tunnel was solo involving a tight squeeze head first in to pitch black, muddy & wet & it was only when I turned on my head torch to be confronted with a mass of large spiders inches away from my face. I didn't spend long in there as my batteries had died within a few minutes & the entry point was resealed for a couple of years until someone took it upon themselves to open it properly in 2009. Asbestos sheeting that once lined the roof section littered the floors, smashed to bits by youths years back, most probably 70's/80's. A dozen or so more visits were made during the time it was open, each time finding something new like graffiti or artefacts & we had a little experiment with creative lighting along the way after really getting back into my photography again.

Asbestos sheeting littering the floor

Lighting the way 

Taking a moment to reflect around halfway inside the tunnel
Evidence of it's WWII use as a deep air raid shelter still remain with blast doors, dogleg sections with baffle walls, hospital sick bay complete with curtain rails & bed frames scattered around. Ladders lead up high to former emergency exit points, now blocked with huge boulders with service tunnels around three feet in height making for an interesting crawl to another ladder higher up. We will focus a lot more on Cann Tunnel in detail next year but in the meantime we have been working on following up extra research from two e-mails we received to build a better history on the tunnel during it's wartime use & as a naval store.

Blast door a few meters away from the north portal

Baffle sections

WWII hospital sick bay

Dividing curtain rail for two sick bays
Bed frames thought to be from the sick bays

One of the small service tunnels

Ladder of mud to the exit point up high above with a constant trickle of water 

Former exit point now blocked with a precariously perched boulder

Did you or a member of your family ever visit/work at the tunnel during the war?

We need your stories & old photographs to add the history to our fast building archives & for possible inclusion in the forthcoming books. Please get in touch via

Until next time...


  1. This is titled Cann Tunnel but I believe that it is the Leigham Tunnel. This was part of the Plymouth to Princetown horse drawn railway. Granite quarried on dartmoor for Nelson's Column & the old London Bridge was transported through here

    Tony Lord

  2. Myself and a schoolfriend got into the tunnel in the early 70s. There used to be a couple of small brick buildings with metal doors, leading to ladders going down, located along Novorrisisk (?) Road. I have a picture of one of these structures somewhere. Somehow, we managed to get in there, but I remember that it was extremely dangerous. When we got down into the tunnel, I have a memory of part of it being used as a storeroom by ASDA. If this is so, there must have been some kind of access from the ASDA store, but to be honest, I don't know if this memory is correct, it is a long time ago. Maybe someone else can confirm this, or not, as the case may be.

    1. im interested in seeing these photos, if you can will you email them to me please: