Archaeologists have discovered the ruins of an 800-year-old Aztec pyramid in the heart of Mexico City that could show the ancient city is at least a century older than previously thought.

Among Mexico's numerous pyramids and archaeological sites ... and before the rise of the Aztec empire, if you're keeping track. Once a powerhouse in Mesoamerica, and a prominent trade center ...

On the edge of Mexico City's famed Zócalo plaza, next to the ruins of the Aztec sacred pyramid known as the Templo Mayor, the remains of an animal—perhaps a dog or a wolf—were discovered.

Scattered throughout Mexico, you'll find the ruins of several ancient civilizations, including those of the Aztec, Maya and Toltec people. Many of these sites feature impressive pyramids standing ...

Archaeologists in Mexico found nearly 200 animal remains beneath the Moon Pyramid in Teotihuacán ... more than a millennium before the Aztec civilization settled in the region.