You are invited to join Old Pueblo Archaeology Center’s “Autumn Equinox Tour to Los Morteros and Picture Rocks Petroglyphs Sites” with archaeologist Allen Dart, on Tuesday, September 22, 2026. This tour will be held from 8:00-11:30 am, departing from near Silverbell Road and Linda Vista Blvd in Marana, Arizona.

The 2026 autumn equinox occurs on Tuesday, September 22, 2025, at 5:05 pm MST (September 23 at 12:05 am Coordinated Universal Time [UTC]) according to https://aa.usno.navy.mil. To celebrate the equinox day (but not the exact time!) and explore ancient people’s recognition of equinoxes and other calendrical events, archaeologist Allen Dart (Old Pueblo Archaeology Center’s executive director) leads this tour to Los Morteros, an ancient village site that includes a Hohokam ballcourt, bedrock mortars, and other archaeological features, and to the Picture Rocks petroglyphs site where the ancient rock imagery includes a solstice and equinox calendar marker, dancing human-like figures, whimsical animals, and other petroglyphs made by people of the Hohokam archaeological culture between 800 and 1100 CE. An equinox calendar petroglyph at the site exhibits a specific interaction with a ray of sunlight on the morning of each equinox regardless of the hour and minute of the actual celestial equinox, so participants in this tour will see that sunlight interaction with the calendar glyph unless clouds block the sunlight. Participants provide their own transportation.

There is a requested $45 donation per person ($36 for Old Pueblo Archaeology Center members), which supports Old Pueblo’s education programs about archaeology and traditional cultures. Registration and prepayment are due 10 days after reservation request or by 5 pm Sunday, September 20, whichever is earlier: info@oldpueblo.org or 520-798-1201.

Flyer: 20260922(v1)LosMorteros&PictureRocksAutumnEquinoxTourFlyer
Caption: Equinox “sun dagger” on spiral petroglyph at Picture Rocks site, Pima County, Arizona, photo by Tom Herrick