The Pyramid of the Moon is the second largest pyramid in modern-day San Juan Teotihuacán, Mexico, after the Pyramid of the Sun. It is located in the western part of the ancient city of Teotihuacan and mimics the contours of the mountain Cerro Gordo, just north of the site. Some have called it Tenan, which in Nahuatl, means "mother or protective stone." The Pyramid of the Moon covers a structure older than the Pyramid of the Sun. The structure existed prior to 200 AD.
The Pyramid's construction between 200 and 250 AD completed the bilateral symmetry of the temple complex. A slope in front of the staircase gives access to the Avenue of the Dead, a platform atop the pyramid was used to conduct ceremonies in honor of the Great Goddess of Teotihuacan, the goddess of water, fertility, the earth, and even creation itself. This platform and the sculpture found at the pyramid's bottom are thus dedicated to The Great Goddess.
Opposite the Great Goddess's altar is the Plaza of the Moon. The Plaza contains a central altar and an original construction with internal divisions, consisting of four rectangular and diagonal bodies that formed what is known as the "Teotihuacan Cross."