Teotihuacán, Ancient Metropolis of Mesoamerica

Containing the third largest pyramid in the world and once home to almost 200,000 people, Teotihuacan was the first metropolis of Mesoamerica. The huge scale of its monuments, its architectural sophistication, and still-vibrant murals set this site apart from the pack for even the most casual admirer of archaeology.

Although scholars aren't sure of the origins of the builders of Teotihuacan, the area was probably first populated around 300 to 100 BC, after the destruction of Cuiculco (south of today's Mexico City) due to the eruption of the Xitle volcano. Perhaps the migrants chose this undulating high plain because of its lack of smoking volcanoes in the immediate vicinity.

The first building blocks of this city were laid around the dawn of the Common Era (AKA the Christian Era). Containing homes for common people as well as royal palaces, administrative and religious buildings, it was larger and more complex than any of its contemporaries in the hemisphere. The first structures erected were the Pyramids to the Sun and the Moon, begun around the year AD 1.

The Pyramids of the Moon and the Sun

One of the most important structures at the site, the Pyramid of the Moon occupies a key position at the north end of the city. This massive and magnificent structure contained royal tombs, possibly including those of the city's founders. Not walled, it was most likely a place where the public congregated for ceremonies. When we visited in October 2009, visitors were allowed to climb only to the first level; however, it still offers a wonderful view of the site and surrounding hills.

Begun about the same time, the Pyramid of the Sun was built near the center point of the sacred part of the city. Comparatively stocky when you compare its height (64 meters/213 feet) to the length of each base (224 meters/746 feet) it is still amazingly large, the third-largest pyramid in the world. It was constructed of fill (dirt, sand, and adobe) covered with rock and then faced with a mixture of limestone, sand, and paint.

What serve today's visitors as steps were originally part of the retaining walls. Sloped panels covered the structure, and on top were a cluster of temples. As opposed to the Pyramid of the Moon---which was added to in stages---the Pyramid of the Sun is thought to have been built in one long haul. Visitors can climb all 244 steps to the top of the structure.

The pyramid's name may be a misnomer. Archaeologists now believe that it was dedicated to the rain god, Tlaloc, and not to a sun god as previously thought. The evidence includes a moat surrounding the gigantic mound as well as child burials at its corners. Children were sacrificed to appease Tlaloc; their frantic cries were believed to bring rain. A cave beneath the great structure simultaneously referred to the womb, the place where life begins, and to death, or burial, where it ends.

More Religious Structures, Palaces, and the Avenue of the Dead

Next to be built, around AD250, the Temple of Quetzalcoatl was connected to the two pyramids by the Avenue of the Dead. Named Calzada de los Muertos by the Aztecs who visited many hundreds of years after this city's demise---the first pre-Hispanic tourists?!---this broad avenue was paved with flat volcanic stones and lined on either side with magnificent structures.

Excavated beginning in 1964, el Palacio de Quetzalpapalotl, the Feathered Butterfly, is one of the best preserved. A residential area for priests and nobles, it is a complex of corridors, rooms, antechambers, and courtyards. Square columns have bas reliefs of birds (profile and front view); the pillars are also embellished with symbols of eyes, butterflies, flames, and quetzal birds. Along lower interior walls are murals that remain strikingly colorful after more than 1,000 years' exposure to the elements. Along one wall, jaguars with elaborate headdresses play conch-shell trumpets while the image of the rain god is repeated inside a series of stars. In an adjacent structure, a line of parrots slyly poke at stylized flowers with their beaks.

Excavation is ongoing. The painted stone panels of the Grupo Mural de la Puma, discovered in 1963, are representative of those that once adorned buildings along both sides of the Avenue of the Dead. Above the felines are circles representing the god Tlaloc, or perhaps an aquatic environment.

At the southern end of the ceremonial center is a large area called La Ciudadela, where at least 15 pyramid bases were built on a huge platform. Most likely the administrative center of the site, la Ciudadela is currently under excavation. The complex was originally surrounded by a wall that afforded privacy for royal residences and private ceremonies. Here a temple dedicated to the feathered serpent, Quetzalcoatl, has one wall adorned with bas relief sculptures of snake heads, the rain god, and feathered shells.

In its heyday, Teotihuacán covered more than 10 square kilometers (3.8 square miles) and was home to nearly 200,000 people. Outside of the ceremonial center and unknown to many visitors, several groups of residences with impressive murals have been partially restored. Individual families shared communal patios and cooking areas. Don't miss Tepantitla, outside the northeast parking lot. This residential area sports an impressive mural of the rain god Tlaloc in heaven, a recreation of which is shown at the Museum of Archaeology in Mexico City. Near the main entrance on the west are another group of semi-restored dwellings.