- **Date of Independence:** July 4, 1776 (as part of the original 13 colonies declaring independence from Britain) - **Date of Annexation to [[United States of America (USA)]]:** December 12, 1787 (2nd state to ratify the Constitution) - **Population (2025):** 13.1 million - **GDP (2025):** $790 billion - **Largest City:** Philadelphia (1.5 million) - **State Capital:** Harrisburg (50,000) - **Historical Note:** Known as the "Keystone State" for its central role in founding America. Declaration of Independence and Constitution signed in Philadelphia. Founded by Quaker William Penn as religious tolerance haven. Liberty Bell, Independence Hall, and major Revolutionary War sites. Birthplace of American democracy.