AZTEC, N.M. — A Colorado historian is leading a team to survey inscriptions left by settlers and others on the ceilings of 900-year-old ruins in northwestern New Mexico.

Fred Blackburn and his team will study the lengthy messages, or graffiti, left at the Aztec Ruins National Monument to gain insight on how others saw the engineering marvel, the Farmington Daily Times reports. Some of those who left inscriptions were white settlers who tried to make sense of the structures, Blackburn said.

Blackburn wants to know the stories of those folks and add historical context to their inscriptions in as many cases as possible.

"We want families (who) have been here for generations and can shed some light on what this place was like 100 years ago," he said. "They were the keepers of that early history."

The monument near the town of Aztec is made of 400 masonry rooms and is an ancestral pueblo structure that dates back to the 11th to the 13th centuries. White settlers named it after mistakenly believing it was built by Aztecs from central Mexico.

Amateur explorations of the ruins began shortly after Anglo settlers began moving into the area in the 1870s, said Blackburn, a former Bureau of Land Management ranger. Blackburn spent years working in the Natural Bridges National Monument in southeast Utah before helping establish the Crow Canyon Archaeological Center near Cortez, Colorado, and the White Mesa Institute at the College of Eastern Utah.

Those early visitors often gained entry to some of the sealed rooms at the ruins by knocking down bricked-up windows or doors, leaving debris scattered several feet deep. They would stand on that rubble while leaving an inscription with a quill pen and ink or lead pencil on the vigas or latillas that make up the ceilings.

Blackburn emphasized he isn't interested in trying to shame anyone into returning any artifacts their ancestors may have removed from the ruins before the site fell under the protection of the American Museum of Natural History and the National Park Service. He wants information, not relics.

Blackburn's team plans to examine 23 of the original and intact rooms at the ruins. It was working on its sixth room earlier this week, a process that got underway in May. He estimated his team would not finish its work until December.

The project is being funded by federal money in the form of a Cooperative Ecosystem Studies Unit grant that is funneled through the firm Archaeology Southwest in Tucson, Arizona.

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