Background
Ciudad de México ("Mexico City" in English) is the capital city of the nation of Mexico.It is one of the largest cities in the world and is classed as a megalopolis as it encompasses one large city that has slowly engulfed other, smaller ones. It is located in the Valley of Mexico, a large valley in the high plateaus at the center of Mexico, about 2,240 meters (7,349 feet) above sea-level, surrounded on most sides by volcanoes towering at 4,000 to 5,500 meters (13,000 to 18,000 feet) above sea-level. Mexico City, as a municipality, was established in 1521 by Hernán Cortéz in the middle of the now drained Lake Texcoco on the ruins of Tenochtitlan, the capital of the Aztec Empire, and of its lesser-known twin city Tlatelolco. The municipality was abolished in 1928, and the name "Mexico City" can now refer to two things.
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