Philadelphia is a city in the Commonwealth of Pennsylvania in the United States. It is the sixth-most-populous city in the United States and the most populous city in the state of Pennsylvania. It is also the second-most populous city in the Northeastern United States, behind New York City. The city is also the economic and cultural center of the greater Delaware Valley along the lower Delaware and Schuylkill rivers within the Northeast megalopolis.
Philadelphia is one of the oldest municipalities in the United States. In the 19th and 20th centuries, it became a major industrial center and a railroad hub. The city grew due to an influx of European immigrants, most of whom initially came from Ireland and Germany. In the early 20th century, Philadelphia became a prime destination for African Americans during the Great Migration after the Civil War. Puerto Ricans began moving to the city in large numbers in the period between World War I and II, and in even greater numbers in the post-war period.
The Philadelphia area’s many universities and colleges make it a top study destination. The city has more outdoor sculptures and murals than any other American city. Fairmount Park, when combined with the adjacent Wissahickon Valley Park in the same watershed, is one of the largest contiguous urban park areas in the United States.
Philadelphia is the home of many U.S. firsts, including the first library (1731), hospital (1751), medical school (1765), national capital (1774), First university in the United States (1779), stock exchange (1790), zoo (1874), and business school (1881). Philadelphia contains 67 National Historic Landmarks and the World Heritage Site of Independence Hall. The city became a member of the Organization of World Heritage Cities in 2015, as the first World Heritage City in the United States.
These amazing black and white photos were taken by Laurence Salzmann that show street scenes of Philadelphia in 1971.