Which is the first US city inducted into the Organization of World Heritage Cities (OWHC)?

Philadelphia is the largest city in the Commonwealth of Pennsylvania and the fifth most populous city in the U.S. (2015 estimate).

Philadelphia has more outdoor sculptures and murals than any other American city. The 67 National Historic Landmarks in the city helped account for its attraction to tourists (over 39 million domestic tourists in 2013).

Philadelphia is known as the birthplace of the U.S. It was here that the founding fathers of the U.S. signed the Declaration of Independence and the Constitution. It is also the home of many U.S. firsts, including the first library (1731), first hospital (1751), first medical school (1765), first Capital of US (1777), first stock exchange (1790), first zoo (1874), and first business school (1881). Because of its arts, culture, and history, Philadelphia, in 2015, became the first US city inducted into the Organization of World Heritage Cities.