When William Penn first sailed up the Delaware River in the fall of 1682, he envisioned the verdant waterfront as a tree-lined promenade bearing his name. Despite a lengthy gestation period attended by every imaginable snag, Penn's Landing has gradually evolved from a warren of rundown docks into the haven its founder imagined: a recreational complex centered on the amphitheater of Great Plaza. The al fresco auditorium is home to more than half of the countless festivals, events and performances presented at Penn's Landing, serving as the locus of annual events ranging from jazz series to dining demonstrations. The venue doubles as a primer on Philly's maritime history, educating visitors via informative markers discussing semaphore flags, Philadelphian neighborhoods, population growth and the geology of the Delaware Basin. -- Julia Clinger (Photo: Jon Stark)