All week long, we've been playing this sound and asking you to guess what exactly it is and where exactly in the Bay Area we recorded it.
This auditory guessing game is part of Audiograph, a crowd-sourced collaborative radio project mapping the Bay Area’s sonic signature. Audiograph tells the story of where you live and the people who live there with you. Every Thursday, we tell you the story behind our weekly mystery sound on Crosscurrents, and here in weekly blog posts.
Listen above for the full answer.
Jane Swenson correctly identified this sound.