Mystery Walls – Bison Weirs?

Around 1980 there appeared an article in the Oakland Tribune about the mystery walls in the East Bay Hills. Michael Harkins and I went an saw them. Here is a very good article on this enigma, this confounding riddle that defies logic. I believe I have come up with the only theory that makes sense.

The American Bison were found in almost every state. I suspect a vast herd made its way to California from Colorado and then migrated up to the Bay Area. Not owning horses, the natives were not able to chase down the Bison, so they built WEIRS, rock walls, and when the bison wandered into them, a line of hunters would close in for the slaughter.

“After meandering throughout the Oakland hills, they head inland towards Mt. Diablo where they lead to mysterious stone circles, up to 30 feet in diameter. In one place the walls form a spiral…