If Market Street is where Philadelphians went to satisfy their mercantile needs, Broad Street is where they addressed their spiritual ones. This was especially true on the northern half, above City Hall. As Philadelphia's middle class migrated northward in the early decades of the 20th century, nearly every faith planted a stone-clad flagship on that famously long, straight street. We know too well how the story has gone in recent years. Many of Broad Street's great religious citadels were torn down, and replaced by fast-food joints, fallow lots, and various other indignities. Others continue to hang on by a shoestring, thanks to the arrival of new denominations that adopted the old buildings and shaped them for their own faiths. But now, in a small, but enormously telling shift in the street's fortunes, one of the old-timers has begun to thrive again. So much so, it is planning a prominent new wing.