A color photograph of the Hollywood Hotel is a rare and wondrous thing. It makes it easier to believe that there actually was a grand old dame of a hotel at the corner of Hollywood Boulevard and Highland Ave—instead of a Gap store. What really makes this circa 1948 photo pop are those three bright yellow taxi cabs parked out front, but can anyone tell me what that yellow box standing on the sidewalk behind the 3^rd one was or what it did?

UPDATE: It’s a call box, if no cabs are present.