Tenochtitlan was built in 1325 on an island in the middle of Lake Texcoco. It became the most powerful city in Mesoamerica, and one of the largest cities in the world, until 1521, when it was destroyed by the Spanish conquerors. Mexico City was built on the ruins of Tenochtitlan. Aztec empire. Tenochtitlan. Peoples of Mesoamerica