Important city in the basin of Mexico, perhaps the first and the most important at that time. It was founded around the year 2100 BC, near the Zacatépetl mountain range and Lake Chalco. At first it was a group of agricultural villages that were also dedicated to fishing. By the year 800 B.C. It seems to have become a complex city and a very important commercial center due to the crossing of roads to the valleys of Toluca and Morelos. It was undoubtedly a religious capital in which the cult of Huehuetéotl, the old god of fire, occupied a prominent place. The name that the Mexica later attributed to it, Where the songs and the dance, denoted that sacred character.

From Cuicuilco, for posterity, the Great Pyramid remained, erected between 800 and 600 BC, with an elliptical plan (Zone A); the Circular Mound of Peña Pobre (Zone B), the Tenantongo Pyramid in the Tlalpan Forest (Zone B) and the circular base construction of the Olympic Village (Zone C). In the centuries that followed, especially in the 20th, Mexico City grew to cover with modern buildings a large part of the land on which there could be, deep down, vestiges of the pre-Hispanic city, so its study and recovery has become very difficult. However, in the explorations carried out, especially in areas that were not covered by lava (Zone A), some weapons (átlatl or dart thrower), pieces of obsidian and stone beads have been recovered; Likewise, it has been possible to rescue burials in which the human remains appear flexed and show cranial deformation.