The old city center or Centro Histórico of Mexico City, around the Plaza de la Constitución, is an area clearly different from the rest of the city. Its colonial and European architecture and narrow cobblestone streets set it apart from the rest of Mexico City. It has an enormous number of stores, street vendors, and especially crowds. Without a doubt, this area is one of the most popular areas in Mexico City.
The Centro Histórico, the original foundation of Mexico City, was built on the ruins of Tenochtitlan, the Aztec empire capital established around 1325 and destroyed by the Spanish in 1521. It contains a lot of old buildings that date back to the 16th century. Due to its importance, it was included in UNESCO's list of world heritage places in 1987.