The largest metropolitan area in Pennsylvania is Philadelphia, with a population of approximately 12.8 million. Philadelphia is part of the Northeast megalopolis, which stretches from Boston to Norfolk, and is one of the busiest shipping centers in the world. Pittsburgh is part of the Great Lakes Megalopolis and is associated with the Midwestern United States and the Rust Belt. The population of these cities is approximately the same as that of the entire state.
The Pocono Mountains run through the northeast corner, while the Appalachian Mountains cut through the center of the state. The state is approximately 60% forested. The state is home to the famed Dutch Country, a cluster of rural counties in the southeast corner. The Amish community there eschew cars in favor of horse buggies. The state is also home to bustling Philadelphia, located along the Delaware River and along the eastern border with New Jersey.
After the decline of mining, the Pennsylvania economy has transitioned to service industries. Large industries in Philadelphia and Pittsburgh have made these two major cities world leaders in healthcare and technology. As a result, many Pennsylvania residents have migrated from foreign countries, bringing cheap labor with them. While the majority of residential growth has taken place in the suburbs, both cities have undergone significant downtown revitalization efforts. These revitalizations are vital for the state's economy and have kept the state's population stable.
The Pennsylvania state capital, Philadelphia, was located in the region around the midpoint of the United States. This allowed it to serve as the unofficial political hub of the nation for the first fifteen years of its history. The Second Continental Congress and the United States Constitutional Convention were held in Philadelphia, and the city became the capital of the Commonwealth for most of the Confederation Era (1776-1787).