The territory under the jurisdiction of the Commissioner of Highways for the purposes of this article shall include all of the Commonwealth, exclusive of that portion thereof that lies within the corporate limits of municipalities, except the jurisdiction of the Commissioner of Highways shall apply to all the territory within municipalities on which signs, advertisements, or advertising structures are visible from the main traveled way of any Interstate System highway, federal-aid primary highway as that system existed on June 1, 1991, or National Highway System highway.