Chihuahua (state, Mexico), state in northern Mexico. Chihuahua is Mexico’s largest state and has one of the nation’s most diversified economies. It is bordered by Texas and New Mexico along the United States border, and by the Mexican states of Sonora and Sinaloa on the west, Durango on the south, and Coahuila on the east.

Two major geographic regions—the central plain in the east, and the Sierra Madre Occidental mountain range in the west—occupy much of the state’s territory. The western plateaus and valleys receive significant rainfall at higher elevations, but most areas of the state receive less than 500 mm (20 in) per year. Pine, spruce, and fir grow in the mountains, while vegetation in the semi-arid central plains regions is sparse and typified by brush and desert plants. The state’s only major river, the Conchos, flows northeast into the Río Grande (known as the Río Bravo in Mexico), which forms Chihuahua’s border with Texas. The spectacular scenery of the mountains has attracted motion-picture companies from the United States for decades, and many westerns have been filmed in Chihuahua. On the other hand, the ruggedness of the terrain has discouraged direct overland communications with neighboring states. Cumbres de Majalaca National Park—featuring forests of pine, juniper, and oak—is located about 40 km (about 25 mi) northwest of Chihuahua. Cascada de Basaseachic National Park, located near the state’s western border, contains the highest waterfall—246 m (807 ft) high—in Mexico. The state covers an area of 245,945 sq km (94,960 sq mi).

Numerous indigenous groups once resided in the region, including members of tribes based in what is now the southwestern United States, such as the Apache, Comanche, and Pima (or Akimel O'Odham). A major indigenous group in modern Chihuahua is the Tarahumara, who live primarily in Sierra Tarahumara, a mountainous region geographically isolated from most of the state. The state’s most important city is Ciudad Juárez, sister city to El Paso, Texas, and one of Mexico’s most populous and fastest growing urban centers. Ciudad Juárez and El Paso share many ecological and infrastructure problems created by rapid economic growth. The capital city of Chihuahua is situated at the center of the state and is the primary commercial and transportation hub for the region. The state’s estimated population in 2008 was 3,359,934.

Chihuahua is one of Mexico’s most economically developed states and has attracted large numbers of immigrants from elsewhere in Mexico. Mining has long been an important economic activity, and the state is still among the nation’s top producers of iron, copper, lead, silver, and zinc. Agriculture, forestry, and ranching are also important, with irrigated farmland producing large quantities of apples, peaches, and nuts that are usually exported to the United States. In recent years, however, manufacturing, commerce, and service industries have become increasingly important. The major north-south highway, which serves as a point of entry from the United States into Mexico, leaves El Paso and passes through Chihuahua, connecting it to the cities of Torreón to the southeast and Durango in the south. A major rail line, the Chihuahua-Pacific, connects Los Mochis on the Gulf of California to Chihuahua. Also known as the Copper Canyon railway, the line has numerous bridges and tunnels along its route, which passes through some of the most rugged and scenic terrain in the country.

Archaeological evidence suggests that the region that is now Chihuahua was first inhabited by humans about 25,000 to 30,000 years ago, when nomadic hunters first entered the region. Spanish explorers first entered the region in the late 1500s; the discovery of silver in the early 1600s attracted settlers and increased economic activity. Chihuahua, along with Durango, formed a frontier province of the during the colonial era. Chihuahua achieved statehood soon after Mexican independence in 1821. The state’s geographic isolation from central Mexico and its proximity to the cultural and economic influence of the United States often combined to make Chihuahua a center of resistance to the Mexican government. The state produced several influential figures during the Mexican Revolution (1910-1920), including Francisco “Pancho” Villa, who figured prominently as a leading revolutionary general. In 1992 Chihuahua became only the second state (after Baja California) to be governed by a candidate from Mexico’s conservative National Action Party.