The Chuska Mountains (Navajo: Chʼóshgai) are an elongate range on the southwest Colorado Plateau and within the Navajo Nation whose highest elevations approach 10,000 feet. The range is about 80 by 15 km (50 by 10 miles). It trends north-northwest and is crossed by the state line between Arizona and New Mexico. The highlands are a dissected plateau, with an average elevation of about 2,740 m (8,990 ft), and subdued topography. The highest point is Roof Butte (36.4601° N, 109.0929° W) at 2,994 m (9,823 ft), near the northern end of the range in Arizona. Other high points include the satellite Beautiful Mountain at 2,861 m (9,386 ft) and Lukachukai Mountains at 2,885 m (9,465 ft), both also near the northern end, and Matthews Peak at 2,911 m (9,551 ft). The San Juan Basin borders the Chuskas on the east, and typical elevations in nearby parts of that basin are near 1,800 m (5,900 ft). The eastern escarpment of the mountains is marked by slumps and landslides that extend out onto the western margin of the San Juan Basin. To the north, the Chuskas are separated from the Carrizo Mountains by Red Rock Valley, which is today commonly referred to as Red Valley.