Northern Arizona is an unofficial, colloquially-defined region of the U.S. state of Arizona. Generally consisting of Coconino County, Yavapai County, Navajo County, and Apache County, it is geographically dominated by the Colorado Plateau, the southern border of which in Arizona is called the Mogollon Rim. Mohave County, located in the northwest of the state, may or may not be considered part of Northern Arizona, depending on local opinions.
Flagstaff is the largest city in Northern Arizona. Other cities in the region include Prescott, Sedona, Page, and Williams. Flagstaff is home to Northern Arizona University and the Lowell Observatory.
Much of the territory is National Forest Service land, parkland, reservations, or other BLM-administered lands. In the East are the very large Hopi and Navajo reservations, parts of which overlap, leading to occasional territorial disputes. In this area travelers may tune their radios to hear native-language broadcasts. Native Americans make up the average of 47.87% in Coconino County, Navajo County, and Apache County. Dozens of Anasazi, Sinagua, and other ruins of the ancient Puebloan people can be found throughout the region.