Blisworth Tunnel Blisworth Tunnel Blisworth Tunnel is a canal tunnel on the Grand Union Canal in Northamptonshire, England, between the villages of Stoke Bruerne at the southern end and Blisworth at the northern end. The northern end is about from the northern end of the Grand Junction Canal at Braunston, Northamptonshire and the southern end about . At 3,076 yards (2,813m) long it is the third-longest navigable canal tunnel on the UK canal network after Standedge Tunnel and Dudley Tunnel (and the ninth-longest canal tunnel in the world). At its deepest point it is "ca."143 feet ("ca."43m) below ground level. The tunnel
Blisworth centuries iron ore and limestone were quarried at Blisworth. A limestone quarry began in 1821 north east of the canal tunnel and was connected to a canal wharf at the west end of the tunnel by horse-drawn tramway. The tramway ran from the quarry, across the Stoke Bruerne Road and above the west end of the tunnel. Trains of loaded wagons descended by gravity and empty ones were pulled up by a horse. There was a chute for filling the canal boats from the stone wagons .The quarry was closed in 1912 or 1913. A trial iron ore quarry operated