Coal fired steam locomotive surrounded by a grove of aspen trees in peak autumn color near Calico, CO. on the Cumbres & Toltec Scenic Railroad train on the 64 mile run between Chama, New Mexico and Antonito, Colorado. The railroad is the highest and longest narrow gauge steam railroad in the United States with a track length of 64 miles. The train traverses the border between Colorado and New Mexico, crossing back and forth between the two states 11 times. The narrow gauge track is 3 feet wide. It runs over 10,015 ft (3,053 m) Cumbres Pass.