U.S. Route 89 (US 89) is a north–south United States Numbered Highway with two sections, and one former section. The southern section runs for from Flagstaff, Arizona, to the southern entrance of Yellowstone National Park. The northern section runs for from the northern entrance of Yellowstone National Park in Montana, ending at the Canadian border. Unnumbered roads through Yellowstone connect the two sections. Before 1992, US 89 was a Canada–Mexico, border-to-border highway that ended at Nogales, Arizona, on its southern end. Sometimes called the National Park Highway, US 89 links seven national parks across the Mountain West. In addition, 14 other national park areas, mostly national monuments, are also reachable from this backbone through the Colorado Plateau, Wasatch Mountains and northern Rockies. National Geographic named US Route 89 the No. 1 Driver's Drive in the world. Route description Arizona US 89 begins at Flagstaff, Arizona. The highway proceeds north passing near Grand Canyon National Park and through the Navajo Nation. Near the Utah state line, the highway splits into US 89 and US 89A. The alternate is the original highway; what is now the main highway was constructed in the 1960s to serve the Glen Canyon Dam and Page. The main branch passes over the Colorado River just south of the dam and Lake Powell and then enters Utah. The US 89A branch turns westward and crosses the Colorado River via the Navajo Bridge at Marble Canyon near Lees Ferry. It then climbs on to the Kaibab Plateau, connecting with Arizona State Route 67 at Jacob Lake which provides access to the North Rim of the Grand Canyon. Just before entering Utah, a junction with Arizona State Route 389 in Fredonia serves the Pipe Spring National Monument. The two highways rejoin in Kanab, Utah. Historically, the route extended south to Nogales and served numerous sites of the National Park System in Arizona. Just north of the Mexican border is the Tumacacori National Monument (now Tumacacori National Historical Park), while further north Saguaro National Monument (now Saguaro National Park) in Tucson was reached. Short links took motorists to the Casa Grande National Monument and the Hohokam Pima National Monument south of Phoenix. In the vicinity of Flagstaff there is a quartet of parks: Tuzigoot National Monument, Walnut Canyon National Monument, Sunset Crater National Monument, and Wupatki National Monument. North of Flagstaff, US 89 offers access to both the South Rim and