listed on Interstate road signs
as a destination
of a particular road. For example, the control cities on Interstate 95
immediately south of Washington
When two cities fairly close together are on an interstate, they can wind up having gunfights over who gets to be the control city. Chesapeake, Virginia Beach, Portsmouth, Newport News, and Hampton all had a major pissing contest over who got to be a secondary control city on Interstate 64 east of Richmond (since Norfolk was the obvious primary control city). They wound up compromising, to the point where every sign on I-64 East once you pass tourist mecca Williamsburg has a different secondary control city.