#0excludeGlossary
Pennsylvania, officially the Commonwealth of Pennsylvania, is a state located in the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Maryland to its south, forming the Mason-Dixon Line, West Virginia to its southwest, Ohio to its west, the Canadian province of Ontario to its northwest via Lake Erie, New York to its north, and the Delaware River and New Jersey to its east. Pennsylvania's most populous city is Philadelphia, and the state capital is Harrisburg. Among all US states, Pennsylvania is the fifth-most populous with over 13 million residents as of the 2020 United States census, the ninth-highest by population density, and the 33rd-largest by land area. The largest metropolitan statistical area is the Philadelphia metropolitan area in southeastern Pennsylvania, also known as the Delaware Valley and centered on Philadelphia, the sixth-most populous U.S. city. Pennsylvania's second-largest metropolitan area, Greater Pittsburgh, is centered in and around Pittsburgh, the commonwealth's second-largest city.
Pennsylvania | |
|---|---|
| Commonwealth of Pennsylvania | |
| Nickname: The Keystone State | |
| Motto(s): Virtue, Liberty, and Independence | |
| Anthem: "Pennsylvania" | |
 Location of Pennsylvania within the United States | |
| Country | United States |
| Before statehood | Province of Pennsylvania |
| Admitted to the Union | December 12, 1787 (2nd) |
| Capital | Harrisburg |
| Largest city | Philadelphia |
| Largest county or equivalent | Philadelphia |
| Largest metro and urban areas | Philadelphia |
| Government | |
| • Governor | Josh Shapiro (D) |
| • Lieutenant Governor | Austin Davis (D) |
| Legislature | General Assembly |
| • Upper house | State Senate |
| • Lower house | House of Representatives |
| Judiciary | Supreme Court of Pennsylvania |
| U.S. senators | John Fetterman (D) Dave McCormick (R) |
| U.S. House delegation | 10 Republicans 7 Democrats (list) |
| Area | |
• Total | 46,055 sq mi (119,283 km2) |
| • Land | 44,743 sq mi (115,883 km2) |
| • Water | 1,300 sq mi (3,400 km2) 2.7% |
| • Rank | 33rd[1] |
| Dimensions | |
| • Length | 283 mi (455 km) |
| • Width | 170 mi (270 km) |
| Elevation | 1,120 ft (340 m) |
| Highest elevation | 3,212 ft (979 m) |
| Lowest elevation (Delaware River at Delaware border) | 0 ft (0 m) |
| Population (2025) | |
• Total |  13,059,432 |
| • Rank | 5th |
| • Density | 292/sq mi (112.7/km2) |
| • Rank | 9th |
| • Median household income |  $73,800 (2023) |
| • Income rank | 28th |
| Demonyms | Pennsylvanian Pennamite Pennsylvanier (Pennsylvania Dutch) |
| Language | |
| • Official language | None |
| • Spoken language | |
| Time zone | UTC– 05:00 (Eastern) |
| • Summer (DST) | UTC– 04:00 (EDT) |
| USPS abbreviation | PA |
| ISO 3166 code | US-PA |
| Traditional abbreviation | Pa., Penn., Penna. |
| Latitude | 39°43′ to 42°16′ N |
| Longitude | 74°41′ to 80°31′ W |
| Website | pa |
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nickname, nicknames.| List of state symbols | |
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| Living insignia | |
| Amphibian | Eastern Hellbender |
| Bird | Ruffed grouse |
| Dog breed | Great Dane |
| Fish | Brook trout |
| Flower | Mountain laurel |
| Insect | Firefly (Colloquially "Lightning Bug") (Photuris pensylvanica) |
| Mammal | White-tailed deer |
| Tree | Eastern hemlock |
| Inanimate insignia | |
| Beverage | Milk |
| Dance | Polka |
| Food | None |
| Fossil | Trilobite |
| Soil | Hazleton |
| State route marker | |
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| State quarter | |
 Released in 1999 | |
| Lists of United States state symbols | |
Pennsylvania was founded in 1681 through a royal land grant to William Penn, the son of the commonwealth's namesake. Before that, between 1638 and 1655, a southeast portion of the state was part of New Sweden, a Swedish colony. Established as a haven for religious and political tolerance, the British colonial-era Province of Pennsylvania was known for its relatively peaceful relations with native tribes, innovative government system, and religious pluralism. Pennsylvania played a vital and historic role in the American Revolution and the ultimately successful quest for independence from the British Empire, hosting the First and Second Continental Congress in Philadelphia, the latter of which formed the Continental Army commanded by George Washington in 1775, during the American Revolutionary War, unanimously adopted the Declaration of Independence the following year. On December 12, 1787, Pennsylvania was the second state to ratify the U.S. Constitution after Delaware.
The Battle of Gettysburg, fought in July 1863 around Gettysburg, was the bloodiest battle of the American Civil War with over 51,000 Union and Confederate casualties, and resulted in a repulsion of the Confederacy's invasion of the North. Throughout the late 19th and 20th centuries, the state's steel production and manufacturing-based economy contributed to the development of much of the nation's early infrastructure, including key bridges, skyscrapers, and military hardware used in U.S.-led victories in World War I, World War II, and the Cold War. In the 21st century, Pennsylvania has garnered the nickname "Cellicon State" for the central role of Philadelphia and Pittsburgh in the development of immunotherapies to treat different cancers.
Pennsylvania's geography is highly diverse. The Appalachian Mountains run through the center of the state, the Allegheny and Pocono mountains span much of Northeastern Pennsylvania, and close to 60% of the state is forested. Although Pennsylvania technically has no oceanic shoreline, it has 140 miles (225 km) of waterfront along Lake Erie and along the tidal Delaware River, the latter of which reaches the Delaware Bay, a marginal bay of the Atlantic Ocean.