Pennsylvania is a state in the northeastern part of the United States. Its nicknames are the Quaker State or the Keystone State. Pennsylvania is 180 miles north to south and 283 miles east to west. Of 46,055 square miles, 44817 square miles are land, 490 square miles are inland waters and 749 square miles are waters of Lake Erie. It is the 33rd largest state in the United States.
The highest point of 3,213 feet above sea level is at Mount Davis, the lowest point is at sea level on the Delaware River, and the approximate mean elevation is 1100 feet.
Pennsylvania has 51 miles of coastline along Lake Erie and 57 miles of shoreline along the Delaware Estuary.
Although Pennsylvania lies entirely within the humid continental zone, its climate varies according to region and elevation. The regions with the warmest temperatures and the longest growing seasons are the low-lying southwest Ohio valley and the Monongahela valley in the southeast. The region bordering Lake Erie also has a long growing season, as the moderating effect of the lake prevents early spring and late autumn frosts. The first two areas have hot summers, while the Erie area is more moderate. The rest of the state, at higher elevations, has cold winters and cool summers.