U.S. Route 163 (also U.S. Highway 163, US 163) is a 200-mile (322 km) U.S. Highway that runs from US 160 northerward to Interstate 70 (I-70) in the U.S. states of Arizona and Utah, although only 64 miles (103 km) from US 160 to US 191 is signed. Additionally, the southernmost 44 miles (71 km) of its length is also within the Navajo Nation. The highway forms part of the Trail of the Ancients National Scenic Byway. The highway cuts through the heart of Monument Valley and has been featured in numerous movies and commercials.
The highway was designated in 1970, combining Arizona State Route 464 and Utah State Route 47 as well as a portion of the old alignment of US 160 in Utah. In 1981, US 191 was routed over the northern section of US 163 from Bluff, Utah to I-70. Utah truncated US 163 at the junction with US 191 with plans of extending it further to the east. This planned route was denied and in 2004, US 163 was extended north over its previous alignment, unsigned in favor of US 191 to I-70.
Route description
Arizona
The southern terminus of US 163 is located at a junction with US 160 south of Kayenta in Navajo County and Navajo Nation. The road continues to the south of this junction as Bureau of Indian Affairs (BIA) Route 591. US 163 heads north from US 160 to the west of the Kayenta Airport as it passes through the town of Kayenta. The highway curves towards the northeast in Kayenta before it curves back towards the north. As it continues towards the north, the highway goes through an s-curve, resulting in a northeasterly heading. US 163 continues this heading as it heads toward Monument Valley and crosses the border into Utah. An 18-mile (29 km) stretch of the highway from approximately 5 miles (8 km) north of the US 160 junction to the Utah border has been designated as a scenic route by the state of Arizona.
Utah
The Utah portion of the highway begins in Monument Valley, in San Juan County. Just after entering Utah the highway junctions with the Monument Valley Visitors center. The highway proceeds northeast until the town of Mexican Hat where the highway both crosses the San Juan River and exits the Navajo Nation. From Mexican Hat, the highway travels due east to towards its signed terminus in Bluff. According to the American Association of State Highway and Transportation Officials (AASHTO), the route continues along with US 191 to I-70, however the portion north of Bluff is not signed. The entire signed length of US 163 in Utah has been designated the Bluff to Monument Valley Scenic byway by the Utah State Legislature and forms part of the Trail of the Ancients National Scenic Byway.
Legally, the Utah section of U.S. 163 is defined at Utah Code Annotated § 72-4-122(3).
