Why: It's a piece of living rock 'n' roll history. And wait until you see the poster collection upstairs.
What: Born as a dance hall, this auditorium dates to 1912. Since then it's been many things, including a roller rink. From the outside it looks like a fortress. But in the late 1960s, under the leadership of impresario Bill Graham, it made its name as a rock concert venue. There have been a few detours since then, but that tradition continues now.
The hall, illuminated by 10 dramatic chandeliers, holds about 1,100 people, most of whom stand on the chairless dance floor. Others sit in the upstairs mezzanine area (better views, easier bar access). The poster collection filling the walls upstairs is a festival of boomer flashbacks: the Grateful Dead, Jefferson Airplane, Santana, Quicksilver Messenger Service, Big Brother and the Holding Company. Tom Petty. Los Lobos. And it's not all graybeards. Younger bands such as the Wood Brothers (who played in March) come, too.