Through most of Tamaulipas and Nuevo León, it is a freeway and is essentially a southern continuation of U.S. Interstate 35.

Highway 85D has wider lanes, offers a more direct route, and is continuously being repaired and repaved.

[4] Federal Highway 85 is a 6-lane divided unrestricted access road from Nuevo Laredo to Monterrey.

Gateway to the Americas International Bridge in Nuevo Laredo is the highway's starting point.

At about midway between Nuevo Laredo and Monterrey, Highway 85 crosses the Sierra Madre Oriental mountain range (at the Paso de Mamulique).