Hunsbury Hill Tunnel is a railway tunnel on the Northampton Loop Line of the West Coast Main Line. The tunnel runs in a straight line from the Briar Hill district of Northampton (north portal: ), England about north by east to the East Hunsbury district south of the town (south portal: ). The tunnel has a single bore with twin tracks and is long. It is about 1 mile south of Northampton railway station and the next station south is Wolverton in Milton Keynes. The tunnel opened together with the rest of the loop line in 1881.