Mexico City

The Zócalo is Mexico City's main plaza. It is built over the site of the old Aztec capital's main square. Many important buildings surround the square, including the National Palace, the Supreme Court of Justice, and, seen here, the huge, ornate National Cathedral.

Capital, industrial, and cultural centre of Mexico, 2,255 m/7,400 ft above sea level on the southern edge of the central plateau; population (2000 est) 8,605,200 (city), 18,327,000 (urban area; the largest urban agglomeration in the world). Over half of the country's manufacturing output originates in the city and its surrounds; industries include iron, steel, chemicals, pharmaceuticals, textiles, and electric and electronic goods. It is one of the world's most polluted cities because of its position in a volcanic basin 2,000 m/7,400 ft above sea level, in which pollutants gather and produce a smog cloud.

The city dates from about 1325, when the Aztec capital Tenochtitlán was founded on an island in Lake Texcoco. This city was levelled in 1521 by the Spaniards, who in 1522 founded a new city on the site. It was the location of the 1968 Summer Olympics.

In 1984, the explosion of a liquefied gas tank caused the deaths of over 450 people, and in 1985 over 2,000 people were killed by an earthquake.

Notable buildings include the 16th-century cathedral, the national palace, national library, Palace of Justice, and the National Autonomous University of Mexico (1551). The Ministry of Education has murals (1923-27) by Mexican artist Diego Rivera.

Mexico City is served by a major international airport and lies at the centre of a network of major roads and railways which links it to the rest of the country.