Post your guesses in the comments section below.
Guess correctly and be crowned "Castro Valley know-it-all" for the week.
Unfortunately, no one was able to correctly guess . The buffalo can be found on a house's fence on the corner of Redwood Road and Seven Hills Road.
Have your own photos around town that you'd like featured in our Castro Valley photo challenge? Send them to email@example.com and see if you can stump our readers!