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
Canal tunnel Canal tunnel A canal tunnel is a tunnel for a (shipping) canal. The longest canal tunnel in the world is the Rove Tunnel in France, currently disused. The proposed Stad Ship Tunnel in Norway, while shorter, will be significantly wider and deeper, as it is designed to accommodate seagoing vessels. The oldest canal tunnel in the world is the Malpas Tunnel also in France, built in 1679. In some canal tunnels the towpath continues through the tunnel. In other cases, especially on English narrow canals, there is no towpath. The horse would be led over the hill and the boat