The enormous elevated landmass spanning much of north and central Mexico is known as the Mexican Plateau, or the Altiplano Mexicano. This feature has served as the historical and cultural center of the nation for millennia. Characterized by its high elevation and vast, relatively flat expanse, the plateau has influenced the country’s climate, population distribution, and agricultural development.
Defining the Mexican Plateau
The Mexican Plateau is a massive high-altitude tableland dominating the country’s interior. It stretches approximately 1,130 kilometers (700 miles) from the United States border south to the Trans-Mexican Volcanic Belt. The plateau is a huge basin flanked by two imposing mountain chains: the rugged Sierra Madre Occidental to the west and the Sierra Madre Oriental to the east. This immense landform covers about 600,000 square kilometers (230,000 square miles), accounting for nearly one-third of Mexico’s total territory.
The northern boundary is marked by the Rio Grande (Río Bravo del Norte), which delineates the international border. The southern boundary is defined by the younger, active volcanic range of the Trans-Mexican Volcanic Belt. The average elevation across the plateau is around 1,825 meters (6,000 feet) above sea level, distinguishing its environment from the coastal lowlands.
Topography and Internal Divisions
The Mexican Plateau is divided into two distinct sub-regions by a low east-west mountain range near Zacatecas. These sections are the arid Mesa del Norte (Northern Plateau) and the more temperate Mesa Central (Central Plateau). The Mesa del Norte is the larger and lower of the two, averaging about 1,100 meters (3,600 feet) above sea level.
The Northern Plateau features “basin and range” topography, characterized by expansive plains interrupted by isolated mountain ridges and depressions. The largest depression is the Bolsón de Mapimí, and much of this northern section is covered by the Chihuahuan Desert. In contrast, the Mesa Central is higher, averaging around 2,000 meters (6,600 feet) in elevation.
The Central Plateau’s topography is generally less rugged and contains numerous intermontane basins and valleys, many of which were originally ancient lakes. This southern section rises gently, reaching up to 2,700 meters (8,850 feet) near the Trans-Mexican Volcanic Belt. The Bajío, located in the northern part of the Mesa Central, is known for its relatively level and fertile terrain.
Geological Formation
The massive elevation of the Mexican Plateau resulted from long-term tectonic forces acting upon the North American Plate. Uplift began approximately 50 million years ago, associated with significant volcanic and earthquake activity. This uplift was a direct consequence of the subduction of the oceanic Cocos Plate beneath the North American Plate along the Pacific coast.
The flanking mountain ranges, the Sierra Madre Occidental and the Sierra Madre Oriental, were elevated as the crust buckled and fractured. The Sierra Madre Oriental was formed by tectonic collisions that also built the Rocky Mountains. As these ranges rose, they created a vast interior basin, or graben, which became the Mexican Plateau.
The geological structure is a tilted block of ancient sedimentary and igneous rocks. Volcanic outpourings, particularly in the southern Mesa Central, deposited thick layers of ash and lava, contributing to the region’s elevation and fertile soil. The Trans-Mexican Volcanic Belt continues to shape the southern edge of the plateau through ongoing seismic and volcanic activity.
Climate and Major Population Centers
The high altitude of the Mexican Plateau creates a moderate climate, significantly cooler than the tropical lowlands. This is particularly noticeable in the Mesa Central, where temperatures are temperate. The climate varies dramatically from north to south, primarily due to latitude and the rain shadow effect of the Sierra Madre Occidental.
The Mesa del Norte is largely arid to semi-arid, receiving limited annual precipitation, which contributes to the Chihuahuan Desert ecosystem. In contrast, the southern Mesa Central receives more rainfall, supporting denser vegetation and intensive agriculture. The combination of fertile volcanic soils and a mild climate made the southern plateau the historical heartland of Mexican civilization.
This favorable environment led to the concentration of major urban centers on the Mesa Central. Mexico City, the nation’s capital, is situated in the Valley of Mexico at about 2,200 meters (7,200 feet). Other prominent cities, including Guadalajara, Puebla, and León, are also located in the valleys of this southern plateau. These cities, and the surrounding agricultural region known as the Bajío, form the demographic and economic core of modern Mexico, with more than half of the country’s population residing within the plateau region.