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
Lapal Tunnel the canal is in good repair and is used by boats accessing Hawne basin. The Lapal Canal Trust is concerned with restoring the lost canal to make it navigable up to the tunnel from both the Halesowen and Selly Oak ends, and originally had a longer term aim of restoring the tunnel. In May 2007 the trust received recommendations from professional consultants, Atkins, that the tunnel should not be restored but replaced by a new up-and-over alignment instead. In February 2012 plans for the regeneration of the Selly Oak area were submitted to Birmingham City Council which included a navigable