Located 75 miles north on Hwy 491 near Cortez, Colorado, Mesa Verde National Park has been designated by te United Nations as a World Heritage Site. Ancestral Puebloans built the cliff dwellings between A.D. 550 and 1300. A museum is open year-round 8:00 a.m. - 5:00 p.m. with extended hours during the summer. The campground is open mid-May to mid-October.