The valley is crossed east-west by State Highway 14, which enters from the east over Cameron Pass, providing a link to the Poudre Canyon and Fort Collins. Highway 14 enters from the west over Muddy Pass which provides access to Steamboat Springs, and to Middle Park in the valley of the Colorado River. It is crossed north-south by State Highway 125, which enters from the north (from Wyoming) along the course of the North Platte. It enters from the south over Willow Creek Pass, providing access to the upper end of Middle Park near Granby. The valley along the Illinois River is the location of the Arapaho National Wildlife Refuge.