Braunston Tunnel ft (2.13 m) beam boats to pass. There are three air shafts along its length. The tunnel passes underground alongside another Grand Union Canal feature, Drayton Reservoir, from which the feeder enters the canal at the east end of the tunnel. Braunston Tunnel Braunston Tunnel is on the Grand Union Canal about 830 yds (760 m) east of Braunston, Northamptonshire, England top lock. It is in the northern outskirts of Daventry, about 2 km east of the village of Braunston. Braunston Tunnel is 2,042 yards (1,867 m) in length. Built by Jessop and Barnes, the tunnel has no towpath and
Whilton Locks Braunston, which was long, and the other to the south at Blisworth, which was long. Despite encountering quicksands in Braunston Tunnel, it was finished on 21 June 1796, and the canal opened to Weedon Bec, around to the south of the locks. Shortly afterwards, it was extended further south to Blisworth, but there were serious problems with Blisworth Tunnel, which had failed in January 1796. William Jessop was the engineer and wanted to abandon the idea of a tunnel. He proposed to build 29 locks to get beyond Blisworth, but was persuaded to try a different alignment by three engineers