A detour is a by pass of the activity area which requires drivers to depart completely from the normal road to follow an alternate route. It is indicated by a Detour Ahead sign and by appropriate detour marker signs.

The CS-1 sign indicates that traffic on the road will be required to follow another road to detour around the activity area. The sign when used, should be placed 400 metres in advance of the start of the detour. When necessary, the CS-1 sign may be added in advance of the CS-1 sign, with the appropriate distance indicated on the sign.