Tollan or Tolan or TolŠn is the name used for the capital city of two empires of Pre-Columbian Mesoamerica; first for Teotihuacan, and later for the Toltec capital of Tula.
Teotihuacan seems to have been the first city known by this name. After the collapse of the Teotihuacan empire, central Mexico broke into various petty states. The Toltec created the first sizable Mexican empire after the fall of Teotihuacan, and their capital was referred to by the same name as a reference to the earlier greatness of Teotihuacan.
"Tollan" was also sometimes used to refer to a great metropolis or major capital. Cholula, for example, was sometimes called "Tollan Cholula", and the Aztec capital of Tenochtitlan was also given this title. The Mixtec translation of this name —uu Co'yo is still the Mixtec name for Mexico City to this day.