The area of Pennsylvania was part of the original territory of the United States. It was chartered in 1681, although New York did not relinquish its claim to the area until the following year. The southern boundary was resolved with the survey of the Mason and Dixon Line in the 1760s. Connecticut had claims to Pennsylvania territory resolved by award of the Continental Congress in 1782. Pennsylvania ratified the U.S. Constitution on December 12, 1787; it was the second of the original 13 states to join the Union. Pennsylvania assumed generally the same boundary as the present state with the acquisition of the Erie Triangle from New York in 1792. Pennsylvania is one of four states that are legally described as a commonwealth.
Census data for Pennsylvania are available beginning with the 1790 census. Any population that was enumerated in the Erie Triangle was included in Pennsylvania, although this area was not legally part of the state until 1792.
See: Geographic Terms & Concepts
Counties & County Equivalents
Interactive Map of Pennsylvania Counties | Static Overview Map of Pennsylvania Counties
There are 67 counties in Pennsylvania. Philadelphia County and Philadelphia city are governmentally consolidated and function as a municipal government. All other counties are each governed by a board of county commissioners.
Pennsylvania has 2,575 county subdivisions known as minor civil divisions (MCDs). There are 1,546 townships with active functioning governments and 1 township, Cold Spring township in Lebanon County, which is an inactive entity. Each township is governed by an elected board of commissioners or a board of supervisors. The 1,015 incorporated places are independent of MCDs and serve as 1,027 county subdivisions. In addition, there is one undefined MCD that consists entirely of water area.
Places (Incorporated Cities, Towns & Census Designated Places (CDPs))
Pennsylvania has 1,764 places; 1,015 incorporated places and 749 census designated places (CDPs). The incorporated places consist of 954 boroughs, 57 cities, 3 municipalities, and 1 town. MCD and place governments have the same power and functions in Pennsylvania. Incorporated places in Pennsylvania are independent of county subdivisions.
Alphabetical List of Cities, Towns, CDPs and Other Populated Places
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q, R | S | T | U, V | W, X, Y, Z
Pennsylvania Civil Features
Pennsylvania Civil Features: Political Subdivisions, Native Areas, Land Grants, etc. - sorted by Census Class Codes.
Metropolitan and Micropolitan Statistical Areas
There are 18 Metropolitan and 17 Micropolitan Statistical Areas in Pennsylvania. PA Metopolitan & Micropolitan Areas
Pennsylvania ZIP Code Tabulation Areas
There are 1,798 ZIP Code tabulation areas (ZCTAs) in Pennsylvania. View Pennsylvania ZIP Codes and ZIP Code Maps.
Pennsylvania has 501 unified school districts. View Pennsylvania Public and Private Schools.
Pennsylvania has 18 congressional districts. An interactive map shows the contact information for each Representative as well as the boundaries for each Pennsylvania district. View Map of Pennsylvania Congressional Districts.
State Legislative Districts
There are 50 state senate districts and 203 state house districts in Pennsylvania.