The North Entrance to the Western Heights was situated at a narrow point of the ridge towards the north-eastern end of the fortress, where the North Military Road completed its more moderate ascent from Dover town. The earliest phase of works on this entrance dates to the Napoleonic period, but further work on the North Entrance to complete and modernise it began in in March 1860 and it was finished in February 1864. This created a more elaborate defensive scheme and perhaps reflects a greater concern with a potential assault from the north. A small outer entrance chamber was constructed on the southern side of the inner ditch and draw bridge, this housed the drawbridge mechanism. (location accurate to the nearest 1m based on available information)