Claim: Miles Teller is American.

Pennsylvania -LSB- pɛnsᵻlˈveɪnjə -RSB- -LRB- Pennsylvania German : Pennsylvaani or Pennsilfaani -RRB- , officially the Commonwealth of Pennsylvania , is a state located in the northeastern and Mid-Atlantic regions of the United States . The Appalachian Mountains run through its middle . The commonwealth borders Delaware to the southeast , Maryland to the south , West Virginia to the southwest , Ohio to the west , Lake Erie and the Canadian province of Ontario to the northwest , New York to the north , and New Jersey to the east .   Pennsylvania is the 33rd largest , the 5th most populous , and the 9th most densely populated of the 50 United States . The state 's five most populous cities are Philadelphia -LRB- 1,560,297 -RRB- , Pittsburgh -LRB- 305,801 -RRB- , Allentown -LRB- 118,577 -RRB- , Erie -LRB- 100,671 -RRB- , and Reading -LRB- 89,893 -RRB- . The state capital , and its ninth-largest city , is Harrisburg . Pennsylvania has 140 mi of shoreline along Lake Erie and the Delaware Estuary .   The state is one of the 13 original founding states of the United States ; it came into being in 1681 as a result of a royal land grant to William Penn , the son of the state 's namesake . Part of Pennsylvania -LRB- along the Delaware River -RRB- , together with the present State of Delaware , had earlier been organized as the Colony of New Sweden . It was the second state to ratify the United States Constitution , on December 12 , 1787 . Independence Hall , where the United States Declaration of Independence and United States Constitution were drafted , is located in the state 's largest city of Philadelphia . During the American Civil War , the Battle of Gettysburg , was fought in the south central region of the state . Valley Forge near Philadelphia was General Washington 's headquarters during the bitter winter of 1777 -- 78 .