Blisworth Tunnel has no tow path inside, but is wide enough for two narrowboats to pass in opposite directions. Work began in 1793, but errors by contractor left a wiggle in the tunnel, and after three years work it collapsed due to quicksand, claiming the lives of 14 men. It was then decided to begin again with a new tunnel. By the time the rest of the Grand Junction Canal had opened between London and Braunston, Northamptonshire in 1800, apart from the crossing of the River Great Ouse, the section of canal from Blisworth to the lower end of Stoke Bruerne locks
Chirk Tunnel completely unlit, it is preferable to use a torch/flashlight when walking through the tunnel, as towards the centre it is pitch black. There is however a wooden handrail along the entire length to prevent walkers falling in the canal. Chirk Tunnel Chirk Tunnel is a canal tunnel near Chirk, Wales. It lies on the Llangollen Canal, immediately northwards of the Chirk Aqueduct. It is long and has a complete towpath inside. The tunnel is designed for a single standard narrowboat, so passing is not possible. The tunnel is straight enough to be able to see if a boat is already