Pennsylvania (the Commonwealth of Pennsylvania) is one of four states of the United States of America that is called a commonwealth. It has given its name to the Pennsylvanian time period in geology. Pennsylvania is called the Keystone State. Pennsylvania is one of the U.S.\'s most historic states. Pennsylvania\'s nickname The Keystone State is quite apt. The capital is Harrisburg, Pennsylvania. Pennsylvania is 180 miles (290 km) north to south and 310 miles (500 km) east to west. Pennsylvania is bisected diagonally by ridges of the Appalachian Mountain chain from southwest to northeast. Pennsylvania has one of the largest seaports in the U.S. on its narrow shore, the Port of Philadelphia. Pennsylvania was hard-hit by the decline of the steel industry and other heavy U.S. industries during the late 20th century. Like all American states, the government of Pennsylvania is separated into an executive, a legislature, and a judiciary, the powers and duties of which are established by the Pennsylvania Constitution. The capital of Pennsylvania is in Harrisburg. Pennsylvania has only one incorporated town, Bloomsburg, the county seat of Columbia County. Pennsylvania has given birth to some of the nation\'s leading popular and rock music groups.. Problems in teenagers can be solved. Troubledteensguide.com provides options for parents and teens in different locations of world. TroubledTeensGuide.com educates the youths' parents about the various Pennsylvania options. More schools and programs are added everyday.