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
Cincinnati and Whitewater Canal Tunnel with wing walls. Upon completion, the tunnel was long, and there was between the ceiling and the underwater bottom of the canal. Unusually, the tunnel included room for a towpath instead of requiring the use of leggers, but the typical canal boat nevertheless relied on manpower while allowing the beasts of burden to climb the hill. As the state's first tunnel of its type, the Cincinnati and Whitewater Canal Tunnel has suffered two separate collapse incidents. The first occurred during the construction process, and six workmen died, while another segment caved in during the 1950s during a project to improve