Blisworth Tunnel sections lined with pre-cast concrete rings. It was also used to test out the materials that were later used on the Channel Tunnel. An unused ring is on display near the south portal. 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
Paw Paw Tunnel expected completion date of July 1838. Lee Montgomery, a Methodist minister who had experience from building the canal tunnel for the Union Canal was awarded the contract on March 15, 1836. Construction on the tunnel began in 1836. Unfortunately for Montgomery, the Irish workers were not skilled at tunnel work, so he obtained English masons, English and Welsh miners, and some "Dutch" [i.e. German] labourers. More unfortunately, this caused ethnic tensions which exploded into violence in 1837 and 1838, specifically between the Irish and everyone else; rioters destroyed the tavern at Oldtown, burned shanties, and the like. There were more