ARCHIVED: This Practice Note has been archived and is not maintained. This Practice Note discusses the common law on highway diversions, explaining that it is the passage from A to B that is important, not the precise piece of ground over which the right to travel is thought to exist, and highway closure by natural causes. Moreover, it explains when a highway on or near to the coast is destroyed by incursions from the sea, the courts will not insist that the authority responsible for its maintenance must restore it to a usable state. Although the common law recognises the force of the maxim ‘once a highway, always a highway’, there are, of course, some exceptions. In R v Secretary of State for the Environment, ex p Burrows; R v Secretary of State for the Environment, ex p Simms, Purchas LJ said: ‘At common law the rule was and remains “once a highway, always a highway”.