Aztec Ruins subtly greet winter solstice

Seeing the light: A Chaco Canyon adventure at the spring equinox 2025

It was the evening after the winter solstice at Aztec Ruins National Monument in northwest New Mexico, near the town of Aztec.

Although we were a day late per the solar calendar, the park service program said the alignment of the setting sun would still show the way ancient Chacoan people would have seen the start of the season of longer days.

“We are doing what people have done for ages: watching the sunset,” Ranger Claire Murphy said, as more than 100 people gathered for a presentation the evening of Dec. 22. The group split into two: one went to the restored great kiva, and the other headed to the shadows along the north wall of the ruins. Since we did not have a time-turner, we chose to head to the shadows with Murphy.

“Most simply, these alignments serve as a calendar,” she said.

At Aztec Ruins, the effect of shadows and light is subtle, much more so than at the solstice events at Chaco Culture National Historical Park, Murphy said. The winter solstice aligns with the north wall ruins as the sun sets, while the summer solstice aligns at sunrise.

“The Aztec West Great House was constructed by ancestral Pueblo people about 900 years ago in alignment with the solstices,” according to a National Park Service news release.

Rangers and volunteers escorted visitors for after-hours viewing at the alignment locations. The walk was much easier than the trek to sites in Chaco Canyon — and much warmer than the vernal equinox event we went to at Chaco Canyon last March. At Aztec Ruins, no reservations were needed for the free winter solstice program.

With the skies mostly clear, visitors saw an alignment of the north wall of Aztec West with the sunset position on the western horizon.

“This back wall of the great house aligns with both the sunrise of the summer solstice and the sunset of the winter solstice every year,” the release said.

During the winter solstice, the sunset location appears to “stand still” in its southernmost point on the horizon for multiple days, thus the Monday program allowed viewers to see the highlights a day after the shortest day of the year, Dec. 21.

The solar alignment also occurs during the summer solstice. Visitors would see the effect looking toward the sunrise.

The Aztec Ruins National Monument is open year-round and it is free to visit the ruins and the visitor center’s museum exhibits. The ruins have a half-mile loop trail, that is mostly paved, and an interpretive trail guide is available. The monument is also designated as a UNESCO World Heritage Site.

The Old Spanish Trail winds through mountains and river valleys past cottonwood trees promising water sources, and wagon wheel tracks guided travelers from Santa Fe to Los Angeles. Ancestral roads lead toward Chaco Canyon past Salmon Ruins, near Bloomfield, as well as north to other Chaco outliers such as Mesa Verde in southern Colorado.

Pets are not permitted among the ruins or on the trails, except in the parking lot and on the Old Spanish Trail section that leads to the Animas River.