Philadelphia, the largest city in Pennsylvania and fifth largest in the country, is located in the southeast part of the state at the junction of the Schuylkill and Delaware Rivers. It is coextensive with Philadelphia County.

Philadelphia, the City of Brotherly Love, was settled in 1681 by Capt. William Markham, who, with a small band of colonists, had been sent out by his cousin, William Penn. Penn arrived the following year with the intention of creating a refuge for the Quakers.

In the period before the American Revolution, the city outstripped all others in the colonies in education, arts, science, industry, and commerce. In 17741776, the First and Second Continental Congresses met in Philadelphia, and, from 17811783, the city was the capital of the United States under the Articles of Confederation. In 1790, it became the nation's capital under the Constitution and remained so until the seat of the federal government moved to Washington in 1800.

Within a half-century of the founding of the nation at Independence Hall, Philadelphia had emerged as a leader in America's Industrial Revolution. Today the steam locomotives and hat factories of the 19th century have been replaced by diverse manufacturing specialties such as chemicals (including pharmaceuticals), medical devices, transportation equipment, and printing and publishing. In the services sector, Philadelphia leads in subsectors such as health services, insurance carriers, legal services, and architecture and engineering services. Philadelphia is also home to branches of the U.S. Mint, the Federal Reserve System, and the Internal Revenue Service.

The city's harbor, one of the largest freshwater ports in the world, is the centerpiece of the AmeriPort facility in south Philadelphia, a major shipping center with rail links to the Midwest and Canada.

The city abounds in landmarks of early American history, including Independence Hall, where the Declaration of Independence was signed, and the Liberty Bell. Other significant tourist attractions are the Philadelphia Museum of Art, the Franklin Institute Science Museum, and the Philadelphia Zoological Gardens.