For those would don't know what a Viaduct is, here is a definition:

"A structure of considerable magnitude, usually with arches or supported on trestles, for carrying a road, as a railroad, high above the ground or water; a bridge; especially, one for crossing a valley or a gorge"

This one is in Lanesboro, PA located in the far north east corner of PA near the NY border. You can [id=42547519;view the sign] that describes this.