High Quality Content by WIKIPEDIA articles! U.S. Route 285 is a north–south United States highway, running 845 miles (1,260 km) through the states of Texas, New Mexico and Colorado. The highway`s northern terminus is in Denver, Colorado, at exit 201 on Interstate 25. Its southern terminus is in Sanderson, Texas at an intersection with U.S. Route 90. It has always had an endpoint in Denver, Colorado, though what is now the northern terminus was once the route`s southern end. Trucking makes up a large portion of the route`s traffic, but for the most part, the road is used for local travel from one town to the next.