CLOAK & DAGGER
It turns out the City of Brotherly Love has a rich past of espionage perfect for the history buff.
Robert Wallace is the former director of the Central Intelligence Agency's Office of Technical Service, founder of the Artemus Consulting Group, and contributor to the CIA's Center for the Study of Intelligence. He has co-authored numerous books, including Spy Sites of Philadelphia, Spy Sites of Washington, DC, and Spy Sites of New York City. He is also co-executive producer of the Netflix series Spycraft.