IT looks like a scene from a World War Two movie with prisoners digging a tunnel out of their camps. Instead it is workers building the Clyde Tunnel in the late fifties and early sixties in Glasgow, when brute strength was still a requirement. To make matters worse, the work was done with compressed air pumped into the two tunnels to keep the water out, which meant that much like deep-sea divers, the workers had to spend an hour decompressing afterwards to avoid "the bends". Two men died when the procedures were not followed precisely.

No idea how it started, but all Glasgow children know that they have to test themselves by holding their breath when they are driven through the tunnel. At 30 mph it will take 57 seconds, so not the hardest trial you will ever face - unless you go through at rush hour when the speed slows down. Of course fathers have been known to slow down deliberately to make it harder. Bad dads.