, officially the Commonwealth of , is a state in the Mid-Atlantic, Northeastern, and Appalachian regions of the .

The Commonwealth is bordered by Delaware to the southeast, Maryland to the West Virginia to the Ohio to the Erie and the Canadian province of Ontario to the northwest,  to the , and New Jersey to the , while the Appalachian Mountains run through its middle.

has 140 miles (225 km) of waterfront along Lake Erie and the Delaware .

The is one of the Thirteen original founding states of the ; it came into being in 1681 as a result of a royal land grant to William Penn, the son of the ’s namesake.

Part of (along the Delaware ), together with the present of Delaware, had earlier been organized as the Colony of New .

It was the second to ratify the  Constitution, on December 12, 1787.

Independence Hall, where the  Declaration of Independence and Constitution were drafted, is located in Philadelphia.

During the American Civil War, the Battle of Gettysburg was fought in the  central  of the .

Valley Forge near Philadelphia was General ’s headquarters during the bitter winter of 1777–78.