Permanently signed detour route

Road classification and signage

A permanently signed detour route is a type of route which is used temporarily during special circumstances. Various areas have developed these systems as part of incident management. The purpose of these routes is to provide a detour in the event that the parent route is impassable, due to either a traffic jams, traffic collision, or road closure. Sometimes these routes are signed as a prefixed or suffixed numbered road, making them a type of special route.

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