An Archaeological Mystery in our Backyard:

Wing, M.R., Iida, K. and Wearing E. (2105) “Stone-by-Stone Metrics Shed New Light on a Unique Stone Alignment at the Point Reyes National Seashore, Marin County, Alta California.”California Archaeology. Vol. 7, No. 2. pp. 245-264. http://www.tandfonline.com/doi/full/10.1080/1947461X.2015.1108565

This project was the subject of a feature article in the Point Reyes Light.

There is a man-made 800-foot stone line on Tomales Point in the Point Reyes National Seashore. Nobody is sure who built it, or why. It cuts across the flat top of Tomales Point, ending where the topography gets steep. It consists of hundreds of granite stones set into the ground with small gaps between them. Many of the stones are too big for one or two people to move without mechanical help. The ends of the line are distinct.

It’s easy to hike right past it without noticing. The Park Service doesn’t mention it in any public brochures or maps. It is hard to see because most of the stones are set into the earth near ground level, and because of a large gap where the trail (an old ranch road) intersects the line.

The line as it exists today has no practical use. It is too low to serve as a fence. The Coast Miwok aren’t generally supposed to have built stone structures. Their houses were made of wood and other plant materials. Also, this site was never a Miwok settlement. You wouldn’t live up here on a windy ridge, exposed to storms and with no fresh water nearby. The Miwok built their villages in valleys and on sheltered beaches.

We have only been able to find a few references to this line in the historical literature. Here’s what two local historians say:

Today hikers encounter this 820-foot-long row of granite stones about 1.5 miles along the Tomales Point trail. The boulders are aligned to Mount St. Helena in the northeast and run to the cliff edge, pointing to the Farallon Islands in the southwest. They are named the Spirit Jumping-Off Rocks by the Coast Miwok tribe, who believe when a person dies their spirit walks west. The rock line is man-made and appears on an 1862 Coast Survey map, just four years after Solomon Pierce began ranching on the point. However, who placed the stones, for what purpose, and when still remains uncertain.

(DeRooy, Carola and Dewey Livingston. Images of America. Point Reyes Peninsula: Olema, Point Reyes Station, and Inverness. Charleston South Carolina: Arcadia Publishing, 2008.)

It took a few years, but we made detailed measurements on hundreds of individual stones and we believe we have solved the mystery, or most of it.  The professionals do too, because we were able to publish our findings in the peer-reviewed journal California Archaeology.

This project was a result of Michael Wing’s participation in a 2009 archaeological expedition to Finland through the National Science Foundation’s PolarTREC Program. It was during this expedition, with the State University of New York and McGill University archaeologists, that he saw firsthand how much you can learn about a site without excavating it. Surveying, mapping, historical sleuthing, and comparisons with other sites are the methods we used here.