Had to change up the location in order to post this story, but the title is accurate.
Of course if you are in San Francisco you need to ride the cable cars at least once. And it is actually not just packed with tourist! People use these to get around since they travel to three of the major locations and up some very steep hills, so it beats walking.
They are cheap to rid, its like $3 or #5, dont remember. But you can get year pass for pretty cheap.
The steep hills make for a good ride, especially since you can stand off the edge!