The Medway Gap is a topographic feature in Medway near Rochester in South East England. It was created when the prehistoric River Medway cut through line of chalk hills now known as the North Downs; other rivers such as the Darent and the Stour have similar features. Its past significance as a means of travel is indicated by the prehistoric Medway megaliths in the area. Today a local rail route and a relatively major road (the A228) utilise the valley. The river here is bridged by the M2 motorway and High Speed 1 viaducts.