Mexico City

Mexico City serves as both the capital and largest city of Mexico, and holds the title of North America's most populous urban center. Recognized as an Alpha world city in the 2024 Globalization and World Cities Research Network ranking, it is a major global hub for culture and finance. The city lies on the high Mexican Central Plateau within the Valley of Mexico, at an elevation of 2,240 meters (7,350 feet). Its administrative structure consists of 16 boroughs, known as alcaldías, which are further divided into neighborhoods.

As of the 2020 census, the city proper—covering 1,495 square kilometers—had a population of 9,209,944, making it Mexico's primate city and the second-largest Spanish-speaking city proper globally, after Lima. The broader Greater Mexico City area, defined by a recent federal and state agreement, counted 21,804,515 residents, ranking as the world's 15th-largest metropolitan area and the second-largest urban agglomeration in the Western Hemisphere, behind São Paulo. In 2011, Greater Mexico City generated a GDP of $411 billion, placing it among the world's most productive urban areas. The city alone contributed 15.8% of Mexico's GDP, while the metropolitan area accounted for roughly 22%. If it had been an independent country in 2013, Mexico City would have ranked as Latin America's fifth-largest economy.

The oldest capital in the Americas, Mexico City is one of only two founded by Indigenous peoples. Its origins trace to Tenochtitlan, a Mexica city established around 1325 on islands in Lake Texcoco. Following the 1521 siege, Tenochtitlan was largely destroyed and then reconstructed according to Spanish urban plans. The municipality of Mexico City was created in 1524, and from 1585 it was officially known by its current name. During the Spanish colonial era, the city functioned as a major political, administrative, and financial center. After Mexican independence, the surrounding territory was organized in 1824 as the nation's first and only federal district (the Distrito Federal, or DF).

Following decades of demands for greater political autonomy, residents gained the right to elect both the head of government and members of the unicameral Legislative Assembly in 1997. Since then, left-wing parties—first the Party of the Democratic Revolution and later Morena—have held both offices. The city has enacted progressive policies, including legal abortion, a limited form of euthanasia, no-fault divorce, same-sex marriage, and legal gender change. On 29 January 2016, the Federal District was officially renamed Ciudad de México, or CDMX. These reforms increased the city's autonomy and altered aspects of its government and political structure, though a constitutional clause still prevents it from becoming a state while it remains the national capital.

Historically, the city was often referred to by the initialism "DF" until around 2013, when "CDMX" became more common. Locally, it is colloquially called simply "México," a usage also seen on road signs and highway names. The informal demonym for residents is chilango, a term once used pejoratively by outsiders to describe a loud, arrogant, or ill-mannered person. In turn, Mexico City residents sometimes dismiss those from elsewhere as living in la provincia ("the provinces"), and many proudly embrace the chilango label. The formal term capitalino is considered more polite and correct but is rarely used.

Mexico City was traditionally known as La Ciudad de los Palacios ("the City of Palaces"), a nickname attributed to Baron Alexander von Humboldt after he visited in the 19th century and wrote that it could rival any major European city. English politician Charles Latrobe also referenced this in his writings. During the colonial period, the city's official motto was "Muy Noble e Insigne, Muy Leal e Imperial" (Very Noble and Distinguished, Very Loyal and Imperial). Under the administration of Andrés Manuel López Obrador (2018–2024), the political slogan la Ciudad de la Esperanza ("the City of Hope") was introduced and briefly adopted as a nickname, but it faded after the subsequent administration of Marcelo Ebrard promoted the motto Capital en Movimiento ("Capital in Movement"), which is not treated as a true nickname.

The earliest evidence of human habitation in the area includes the "Peñón woman" and remains found in San Bartolo Atepehuacan (Gustavo A. Madero), initially believed to date to the lower Cenolithic period (9500–7000 BC). A 2003 study, however, placed the Peñón woman's age at 12,700 years (calendar age), making her one of the oldest human remains discovered in the Americas. Analysis of her mitochondrial DNA suggests Asian, European, or Aboriginal Australian origins.

The region was a destination for Teochichimeca migrations during the 8th and 13th centuries, which gave rise to the Toltec and Mexica (Aztec) cultures. The Mexica arrived around the 14th century, settling first on the lake's shores. The city of Mexico-Tenochtitlan was founded by the Mexica in 1325 or 1327 on an island in the center of the Valley of Mexico's inland lake system, sharing the area with the smaller city-state of Tlatelolco.