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
Greywell Tunnel and so avoid the possibility of closure under the Railway and Canal Traffic Act 1888. Harmsworth, the last trader working on the canal, bought the canal in 1923, but only the lower section up to Woking was used. The tunnel was finally closed when part of the roof collapsed in 1932, after which the canal to the west, including Basingstoke Wharf, was sold. It was still possible for canoeists to get through the tunnel until the late 1950s, but the blockage is now total. The tunnel is of interest for its bat populations: it has more roosting bats than any