Pennsylvania

I

Introduction

Pennsylvania, in full, Commonwealth of Pennsylvania, one of the north-eastern states of the United States, bordered on the north by Lake Erie and New York; on the east by New York and New Jersey; on the south by Delaware, Maryland, and West Virginia; and on the west by West Virginia and Ohio. The Delaware River forms the entire eastern boundary of the state.

Pennsylvania entered the Union on December 12, 1787, as the second state. It played a central role in the birth of the United States; both the Declaration of Independence and the Constitution of the United States were drawn up and signed in the state, at Philadelphia. Since colonial times Pennsylvania has been an important agricultural state, and it later became a major commercial, manufacturing, and mining state as well. In the early 1990s Pennsylvania remained a national leader in both manufacturing and mining output. President James Buchanan was born in Pennsylvania. The name of the state was probably coined by Charles II of England and combines the surname of Admiral William Penn, the father of William Penn, to whom the king granted the colony in 1681, and sylva (Latin, “wood”). Pennsylvania is known as the “Keystone State”.

II

Land and Resources

Pennsylvania has an area of 118,515 sq km (45,789 sq mi). The state is roughly rectangular in shape, and its extreme dimensions are 254 km (158 mi) from north to south and 502 km (312 mi) from east to west.

A

Physical Geography

Pennsylvania offers distinct contrasts in topography and soils, incorporating seven landform regions from the Eastern Great Lakes Lowland in the north-west to the Atlantic Coastal Plain in the south-east. Those are: the Eastern Great Lakes Lowland, the Appalachian Plateau, the Ridge and Valley Region, the Great Valley, the Blue Ridge Mountains, the New England Lapland, and the Atlantic Coastal Plain.

The Eastern Great Lakes Lowland is a narrow, level region, bordering on Lake Erie. An escarpment separates this region from the higher Appalachian Plateau, which is sometimes known in Pennsylvania as the Allegheny Plateau. The plateau extends across northern and western Pennsylvania and constitutes about half the state’s area. The north-eastern part of this region is known locally as the Pocono Mountains; the most rugged portion is the Allegheny Mountains in the south.

On the eastern side of the Allegheny Front is the Ridge and Valley Region, made up of ridges separated by broad valleys. Elevations reach a maximum of about 760 m (2,500 ft), with ridges generally rising some 180 to 210 m (600 to 700 ft) above the valleys. In the eastern part of the region is the Great Valley; about 24 km (15 mi) wide, it consists of the Cumberland, Lebanon, and Lehigh valleys.

To the east lies the Piedmont Plateau, a region of low elevation ranging from about 30 to 150 m (100 to 500 ft). In the state’s south-eastern corner lies a narrow strip of the Atlantic Coastal Plain, separated from the Piedmont Plateau by the fall line.

Principal rivers are the Delaware, Susquehanna, and Ohio, with their tributaries, the Lehigh, Schuylkill, Juniata, Allegheny, and Monongahela. The state has more than 300 lakes, most of them small; many are in the glaciated north-western region.

B

Climate

Pennsylvania has a humid continental climate, characterized by large temperature differences between the summer and winter months. The average annual temperature ranges from 8.3° C (47° F) in the north-central part of the state to 13.9° C (57° F) in the south-east. The recorded temperature has ranged from -41.1° C (-42° F) in 1904 to 43.9° C (111° F) in 1936.