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
Sapperton Canal Tunnel workmanship, as it had to be closed for ten weeks after only a year, while repairs were carried out. It was superseded as the longest canal tunnel in England in 1811 by the Huddersfield Narrow Canal's Standedge Tunnel, which was long when built, later extended to to accommodate the adjacent railway tunnel, and remains the highest, longest and deepest canal tunnel in Britain - though, unlike Sapperton, Standedge can only accommodate . Strood Tunnel on the Thames and Medway Canal was also longer at when it opened in 1824, but was cut in two in 1830 by opening out a