Navajo section, Physiographic section in northeastern Arizona, US.

The Navajo Section is the largest of the six sections of the Colorado Plateaus, spanning northeastern Arizona and northwestern New Mexico. It consists of broad rolling plains, shallow river valleys that are dry most of the year, sandstone tablelands, eroded rock formations and cuestas. The section is named after the Navajo Nation, whose reservation covers about half of its area.

The Navajo Section is a physiographic unit of the Colorado Plateaus, named for the Navajo Nation, whose reservation covers about half its area. Its rocks are mainly horizontal sandstone beds with shale sequences of Late Cretaceous and early Cenozoic age. Near Four Corners, the Hogback is a steeply tilted monocline trending southwest from where the San Juan River enters the San Juan Basin.

The section takes its name from the Navajo Nation, which occupies about half of its territory. The Defiance Plateau lies in the central part, and Monument Valley, with its sandstone witness hills, sits on the northern edge along the Utah border. The Painted Desert covers much of the Black Mesa Basin in the west.

The region spans elevations from about 4,700 feet (1,430 meters) near Four Corners to over 9,900 feet (3,000 meters) at Chromo Mountain. Visitors should prepare for varying altitude conditions and diverse terrain.

The Hogback is a steeply tilted monocline running southwest from where the San Juan River enters the section, near Four Corners. West of it, the San Juan Basin exposes the Fruitland and Menefee Formations, and stepped high stream terraces above the river mark abandoned Pleistocene flood plains.