Canyon Trail Park Petroglyph Boulder CA-CCO-152
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Canyon Trail Park Petroglyph Boulder CA-CCO-152


Canyon Trail Park Petroglyph Boulder
20+ bedrock mortars and 175+ cupules on one chlorite blueschist boulder.
Elevation 141 ft.
CA-CCO-152

This rock is in Canyon Trail Park on a branch of Baxter Creek. Baxter Creek flows into the Bay near Stege, a long-vanished neighborhood on the old shoreline of San Francisco Bay, northwest of Albany hill. Some of the Bay Area’s largest shellmounds once stood in Stege.

Rock art specialists believe the first cupules pecked into this rock date back thousands of years to a time before the Ohlone, when Hokan speakers lived along Baxter Creek. The rock may have had a ritual or ceremonial use. Bedrock mortars ground into it may date from the later Ohlone occupation. See Canyon Trail Petroglyphs for more details. Also see Canyon Trail excavation for a discussion of the excavation of this site. Drawings of the above and below ground cupule arrays are very interseting.

Looking at the boulder. A 1949 survey found other cupule rocks in the area. Where are they now?


Mortars and cupules.

Photograph by Bob Bardell

We believe the trinomial for this site is CA-CCO-152.