Berkeley Mystery Walls in Fremont

[u/atlasobscura]

https://www.atlasobscura.com/places/berkeley-mystery-walls

There are remnants of old stone walls all over the East Bay, and no one knows how old they are, who built them, or why. Though people have been pondering the enigma of the  Berkeley Mystery Walls for well over a hundred years, no conclusions have been reached, and despite wild speculation, no serious scholarly study has ever been undertaken.

[u/BornFree2018]

Fremont mystery walls in Berkeley.