Mexico, in full United Mexican States (Spanish Estados Unidos Mexicanos), federal republic in North America. Mexico is the fifth largest country in the Western Hemisphere and is rich in natural resources such as petroleum and natural gas. Mexico’s efforts to develop and modernize its economy—one of the 15 largest in the world—have been slowed by the nation’s rugged terrain, limited farmland, a rapidly growing population, and a series of economic crises. The nation’s capital, Mexico City, is one of the largest cities in the world. In Latin America, only Brazil has a larger population than Mexico.

Mexico is bordered by the United States on the north, the Pacific Ocean on the west, the Gulf of Mexico and the Caribbean Sea on the east, and Guatemala and Belize on the south. It is characterized by an extraordinary diversity in topography and climate and is crossed by two major mountain chains, the Sierra Madre Occidental and the Sierra Madre Oriental. The high central plateau between these two mountain ranges historically funneled most of the human population toward the center of this region. Mexico features volcanic peaks, snow-capped mountains, tropical rain forests, and internationally famous beaches. Mexico City is an enormous metropolitan area and dominates the rest of the country’s culture, economy, and politics. Nearly one-fifth of the nation’s population lives in the immediate vicinity of the capital. Mexico City is also a central hub for Mexico’s transportation network—including railroads, highways, and airlines.