Teotihuacán

A city older than its name

Perhaps a hundred thousand people once lived in the city laid out here, fifty kilometres north-east of Mexico City: about 21 square kilometres of rigid grid around a central avenue two and a half kilometres long, at its height between roughly 100 BCE and 650 CE, one of the largest cities in the world at the time. No writing system that anyone can read has been recovered from it.

We do not know what its builders called it, what language they spoke, or what they called themselves.

That is not a rhetorical flourish. The Aztecs arrived here more than seven centuries after the city was abandoned, found it already in ruins, and gave it the Nahuatl name Teotihuacan, usually rendered as the place where the gods were created. The names we use for its two great pyramids, the Sun and the Moon, are Aztec names for buildings whose original purpose and dedication are unknown. No decipherable writing system has been recovered that would tell us otherwise.

The city was multi-ethnic. Excavated neighbourhoods show distinct Zapotec, Maya and Gulf Coast communities living in their own compounds within the grid, each maintaining their own pottery, burial practices and architecture. Teotihuacan was not one people. It was a city that pulled people in.

The tunnel under the Feathered Serpent

In 2003, heavy rain opened a sinkhole at the foot of the Temple of the Feathered Serpent. Beneath it ran a tunnel, sealed deliberately around 1,800 years ago, extending over a hundred metres under the pyramid.

What excavation found inside it is the strangest material from the site: thousands of objects including seashells, rubber balls, jade figurines, jaguar remains, and walls coated with powdered pyrite and magnetite that would have glittered in torchlight. Sections of the tunnel floor were laid out with what has been interpreted as a miniature landscape, including pools of liquid mercury, a substance that had to be produced by heating cinnabar and that has no practical function here at all.

The chambers at the end of the tunnel were expected to hold a royal burial. So far, no ruler's tomb has been confirmed.

The sky here

At 19.69° N, the city's main axis runs about 15°25’ to 15°28’ east of north. That holds for the Avenue of the Dead, the Pyramid of the Sun and most of the central buildings, across centuries of construction. Around the Ciudadela a second group of alignments runs about 16.5° off the east-west line. The grid is not one decision. It is at least two.

The most detailed survey I could find is Ivan Šprajc’s, published in 2000. He measured the Pyramid of the Sun's east-west axis and found it points at sunsets on about 30 April and 13 August. The longer interval between those two dates is 260 days, the length of the Mesoamerican ritual count, and the dates fall roughly 52 days either side of the summer solstice. His proposal is that they marked stages of a ritual maize cycle, and that the Ciudadela’s alignments added further sunrise dates that divide the 260-day interval into multiples of 20 days.

It is worth seeing what Šprajc rejects. An earlier reading tied the Ciudadela to the Pleiades. He argues against it because the same declinations were kept for about 1,500 years of building, which fits the sun and does not fit a star whose rising point drifts. He also says the 260-day intervals “by no means support” a fixed 260-day cycle. A date that falls on an alignment shows the geometry. It does not show that anyone stood waiting for it.

Two details keep the question honest. Šprajc argues that the Pyramid of the Sun’s north-south axis was deliberately set on the summit of Cerro Gordo, but the Avenue of the Dead itself, as an earlier observer noted, points just left of the main peak. And the cave beneath the Pyramid of the Sun, once argued to have fixed the site, has been shown by geophysical survey to be entirely man-made, so something else chose the place.

Who ruled it? Two readings of one silence

Almost every comparable Mesoamerican city produces portraits of named rulers, dynastic monuments and royal tombs. Teotihuacan has produced essentially none. The question is what that absence means, and the literature splits cleanly.

Reading one: strong rulers, hidden from us. The Temple of the Feathered Serpent was built with the sacrifice of some 200 men and women, which Saburo Sugiyama’s study treats as evidence of state power. Murals show processions of armed, richly dressed figures. Burials in the three main pyramids include bound captives. A planned city of this size, with forced resettlement and large public works, looks like central control.

Reading two: collective government. There are no ruler tombs, no royal portraiture, no dynastic stelae and no inscriptions naming kings. The city’s apartment compounds were built by their own occupants. Its mural art avoids showing one person subjugating another, and later Aztec accounts describe co-rulers. A 2014 paper by Froese, Gershenson and Manzanilla built a model in which cooperation emerges without a central ruler if communal rituals periodically reset the system. They present it as a proof of concept, not as proof of what happened here.

Neither reading explains everything. Strong rulers do not explain the missing portraits. A council does not obviously explain 200 sacrificed people placed under a pyramid.

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