Wupatki and the Volcano That Built a City

Around ten eighty-five CE, a cinder cone north of present-day Flagstaff erupted. The Sunset Crater volcano sent a sub-Plinian column of ash twenty to thirty kilometers into the sky and blanketed more than two thousand square kilometers of northern Arizona with pumice and lapilli. It forced the Sinagua people who lived in the shadow of the San Francisco Peaks to flee.

They came back. Volcanic ash, it turned out, acts as a moisture-retaining mulch, reducing evaporation from the soil. A desert landscape that had been borderline farmable became genuinely productive. That fact spread. Over the following decades, people converged on the ash fields from multiple directions: Sinagua from the highlands, Cohonina from the west, Kayenta from the north and east. Over the following century, roughly two thousand people moved into a region that had been nearly empty before the eruption.

At Wupatki, they built in Moenkopi sandstone. The main pueblo grew to more than one hundred rooms and included the northernmost ballcourt yet discovered in North America, a detail that points to cultural connections with Mesoamerican traditions hundreds of miles to the south. The site also held a community room large enough to suggest it served surrounding villages as a gathering place, perhaps a market or ceremonial center.

By eleven eighty-two, about eighty-five to one hundred people lived in Wupatki Pueblo itself. By twelve twenty-five, the site was permanently abandoned. The departure was gradual, not sudden, and the people did not vanish: they dispersed into communities that would become modern Hopi, Zuni, and other Pueblo peoples. Hopi clan members still visit Wupatki today, not as tourists but as descendants, tracing the route their ancestors walked.