Then the highway enters Pueblo West on its way to intersect with State Highway 45. Highway 50 enters Pueblo, the home of the annual Colorado State Fair, as a six-lane divided highway and joins Interstate 25. Pueblo is at the edge of the Rocky Mountains, the beginning of the plains of southeastern Colorado. As the highway heads east across the plains, it generally follows the path of the Arkansas River until it reaches Kansas. Along the route it passes through a several small communities including Fowler, Rocky Ford and La Junta. Just beyond La Junta, the highway passes Bent's Old Fort National Historic Site where travelers can find information about life on the plains. The highway continues on to Las Animas, Colorado, home of Boggsville National Monument, and Lamar. Between Pueblo and Kansas, Highway 50 intersects with a number of state highways and U.S. highways. The U.S. highways are U.S. Highway 350, 287, 385 and 400. It runs concurrently with 287 and 385 for short distances and with 400 from Granada, Colorado, to Dodge City, Kansas, a distance of . U.S. route 50 in Colorado ends at the Kansas state line, about east of Holly, Colorado, from the Utah border. Holly has the lowest elevation of any town in Colorado at .