San Francisco's flying car, circa 1920S

This 1920 photo was taken at the corner of Hoffman and 23rd St., in San Francisco's Noe Valley, on what looks like a rather foggy day. Clearly, geeks in San Fran have been trying to build flying cars for a pretty long time.

You can see this photo, along with many other historical photos of the Bay Area, at the UC Berkeley Archives. (H/T: @SF_historian)