Flagstaff is a city in and the county seat of Coconino County in northern Arizona, in the southwestern United States. In 2015, the city's estimated population was 70,320. Flagstaff's combined metropolitan area has an estimated population of 139,097. The city is named after a ponderosa pine flagpole made by a scouting party from Boston to celebrate the United States Centennial on July 4, 1876.Flagstaff lies near the southwestern edge of the Colorado Plateau, along the western side of the largest contiguous ponderosa pine forest in the continental United States. Flagstaff is located adjacent to Mount Elden, just south of the San Francisco Peaks, the highest mountain range in the state of Arizona. Humphreys Peak, the highest point in Arizona at 12,633 feet, is located about 10 miles north of Flagstaff in Kachina Peaks Wilderness.Flagstaff's early economy was based on the lumber, railroad, and ranching industries.