Post your guesses in the comments section below.
Guess correctly and be crowned "San Lorenzo know-it-all" for the week.
Congratulations to Mike for correctly guessing The wheel-like object is part of the facade of on Hesperian Boulevard.
Have your own photos around town that you'd like featured in Castro Valley Patch's photo challenge? Send them to firstname.lastname@example.org and see if you can stump our readers!