The state's total area is 121,66 square miles. The eastern border of New Mexico lies along 103° W longitude with the state of Oklahoma, and three miles (5 km) west of 103° W longitude with Texas. On the southern border, Texas makes up the eastern two-thirds, while the Mexican states of Chihuahua and Sonora make up the western third, with Chihuahua making up about 90% of that. The western border with Arizona runs along the 109° 03' W longitude. The 37° N latitude parallel forms the northern boundary with Colorado. The states New Mexico, Colorado, Arizona, and Utah come together at the Four Corners in the northwestern corner of New Mexico. New Mexico, although a large state, has little water. Its surface water area is only about 250 square miles. New Mexico's average precipitation rate is only 15 inches a year.

The landscape ranges from wide, rose-colored deserts to broken mesas to high, snow-capped peaks. Despite New Mexico's arid image, heavily forested mountain wildernesses cover a significant portion of the state, especially towards the north. The Sangre de Cristo (Blood of Christ) Mountains, the southernmost part of the Rocky Mountains, run roughly north-south along the east side of the Rio Grande in the rugged, pastoral north. The most important of New Mexico's rivers are the Rio Grande, Pecos, Canadian, San Juan, and Gila. The Rio Grande is the third longest river in the U.S. It's also the state's main river.

Cacti, yuccas, creosote bush, sagebrush, and desert grasses cover the broad, semiarid plains that cover the southern portion of the state.

The Federal government protects millions of acres of New Mexico as national forests including:

• Carson National Forest

• Cibola National Forest (headquartered in Albuquerque)

• Lincoln National Forest

• Santa Fe National Forest (headquartered in Santa Fe)

Other protected lands include the following national monuments:

• Aztec Ruins National Monument at Aztec

• Bandelier National Monument in Los Alamos

• Capulin Volcano National Monument near Capulin

• Carlsbad Caverns National Park near Carlsbad

• Chaco Culture National Historical Park at Nageezi

• El Camino Real de Tierra Adentro National Historic Trail

• El Malpais National Monument in Grants

• El Morro National Monument in Ramah

• Fort Union National Monument at Watrous

• Gila Cliff Dwellings National Monument near Silver City

• Old Spanish National Historic Trail

• Pecos National Historical Park in Pecos

• Petroglyph National Monument near Albuquerque

• Salinas Pueblo Missions National Monument at Mountainair

• Santa Fe National Historic Trail

• White Sands National Monument near Alamogordo

Visitors also frequent the surviving native pueblos of New Mexico. Tourists visiting these sites bring significant monies to the state. Other areas of geographical and scenic interest include Kasha-Katuwe Tent Rocks National Monument and the Valles Caldera National Preserve. The Gila Wilderness lies in the southwest of the state.