My Master’s thesis research explored the unlikely second wave of rapid transit planning that occurred at mid-century in the United States. One of those plans, from 1956, proposed a massive rapid transit system for the nine counties of the Bay Area. This transit diagram imagines what the Bay Area Rapid Transit system might have looked like had that vision ever come to fruition. Of course, the chances of this system being built were less than slim. But the response to this map on blogs including Ten Times One, Laughing Squid, Muni Diaries, and Mission Mission make it clear that it the dream, for some of us, is a tantalizing one.