Tenochtitlan, the capital of the Aztec Empire, was founded by the Aztec or Mexica people around 1325 C.E. According to legend, the Mexica founded Tenochtitlan after leaving their homeland of Aztlan at the direction of their god, Huitzilopochtli. Huitzilopochtli directed them to build where they saw an eagle perched on a cactus, eating a snake. When they saw this exact scene on an island (located in what was once Lake Texcoco), they interpreted it as a sign from their god and founded Tenochtitlan on that island.

The Aztec region of Mesoamerica, called Anáhuac, contained a group of five connected lakes. The largest of them was Lake Texcoco. The Aztec built their capital city, Tenochtitlan, on Lake Texcoco. Built on two islands, the area was extended using chinampas—small, artificial islands created above the waterline that were later consolidated. Tenochtitlan eventually reached an area of more than 13 square kilometers (five square miles). Causeways that doubled as dikes connected the island to the mainland and separated freshwater from salt water, protecting the chinampas.

Tenochtitlan was laid out symmetrically, with four sectors separated by four causeways or canals surrounding the central area. This central area was where the temple of Huitzilopochtli, temples for other gods, and the rulers’ palaces lay. Each of the four sectors had its own services, including a religious precinct, and was occupied by craftspeople like weavers, sculptors, and potters.

The center of the city was known as the Templo Mayor. Atop the single complex were two temples, one for Tlaloc, the god of rain, and one for Huitzilopochtli, the god of the sun and war. The Templo Mayor precinct was the location in which the Aztec practiced both bloodletting (offering one’s own blood) and human sacrifice.

The Spanish conquistadors, aided by an alliance of Indigenous peoples, laid siege to the Aztec capital for 93 days, until the Mexica surrendered on August 13, 1521. A great deal of Tenochtitlan was destroyed in the fighting, or was looted, burned, or destroyed after the surrender. The leader of the conquistadors, Hernan Cortés, began the construction of what is now known as Mexico City among the ruins. Lake Texcoco was ultimately drained, and much of Mexico City rests in the lake basin.