SDCL § 32-29-2: Stop and yield signs to designate through highways--Visibility at night.

The Department of Transportation with reference to state highways and local authorities with reference to highways under their jurisdiction may designate main traveled or through highways by erecting at the entrances thereto from intersecting highways stop or yield signs. All such signs shall be illuminated at night or so placed as to be illuminated by headlights of an approaching vehicle.