Penn State Great Valley will host a free screening of “Growing Cities,” a documentary that examines urban agriculture as a way to revitalize cities and provide local food to its residents on Wednesday, October 1 at 6:30 p.m. Following the screening, the filmmaker and producer, Dan Susman, will discuss the film and lead a discussion on urban agriculture and sustainable food supplies for a growing world population. The event is sponsored by Penn State Great Valley’s Sustainability program.