“Autumn Equinox Tour to Los Morteros and Picture Rocks Petroglyphs Sites”
September 22 @ 8:00 am - 11:30 am
Join Old Pueblo Archaeology Center’s “Autumn Equinox Tour to Los Morteros and Picture Rocks Petroglyphs Sites” with archaeologist Allen Dart on Monday, September 22, 2025. This tour will depart at 8:00 am from near Silverbell Road and Linda Vista Blvd. in Marana, Arizona. There is a $45 requested donation per person ($36 for Old Pueblo Archaeology Center members), which supports Old Pueblo’s education programs about archaeology and traditional cultures.
The 2025 autumn equinox occurs on Monday September 22, 2025 at 11:19 am Arizona/Mountain Standard Time (same as Pacific Daylight Time; 6:20 pm Greenwich Mean Time). 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 Picture Rocks, where ancient petroglyphs include a solstice and equinox calendar marker and depict dancing human-like figures, whimsical animals, and other rock images made by Hohokam Indians between 800 and 1100 CE. An equinox calendar petroglyph at Picture Rocks 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.
Registration and prepayment are due 10 days after reservation request or by 5 pm Saturday September 20, whichever is earlier: 520-798-1201 or info@oldpueblo.org.
Flyer: 20250922(v1)LosMorteros&PictureRocksAutumnEquinoxTourFlyer
Caption: Equinox “sun dagger” on spiral petroglyph at Picture Rocks site, Pima County, Arizona, photo by Tom Herrick