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
Dudley Tunnel the tunnel pass through a dolerite known locally as Rowley Rag; and through Coal Measures rocks. The Netherton Tunnel follows a parallel route 1½ miles to the south east; it is much larger and has twin towpaths running through it. It was built to ease congestion in the Dudley Tunnel. Dudley Tunnel Dudley Tunnel is a canal tunnel on the Dudley Canal Line No 1, England. At about long, it is now the second longest canal tunnel on the UK canal network today. (Standedge Tunnel is the longest, at , and the Higham and Strood tunnel is now rail only).