The United States Constitution is signed at Independence Hall in Philadelphia, bringing the Constitutional Convention to an end.

The Constitution of the United States is the supreme law of the United States of America. It superseded the Articles of Confederation, the nation's first constitution, on March 4, 1789. Originally including seven articles, the Constitution delineates the frame of the federal government.

The Signing of the United States Constitution occurred on September 17, 1787, at Independence Hall in Philadelphia, Pennsylvania, when 39 delegates to the Constitutional Convention, representing 12 states, endorsed the Constitution created during the four-month-long convention. In addition to signatures, this endorsement, the Constitution's closing protocol, included a brief declaration that the delegates' work has been successfully completed and that those whose signatures appear on it subscribe to the final document. Included are, a statement pronouncing the document's adoption by the states present, a formulaic dating of its adoption, along with the signatures of those endorsing it. Additionally, the convention's secretary, William Jackson, added a note to verify four amendments made by hand to the final document, and signed the note to authenticate its validity.

Independence Hall is a historic civic building in Philadelphia, Pennsylvania, where both the Declaration of Independence and the Constitution of the United States were debated and adopted by the Founding Fathers of the United States. The building, which is the centerpiece of Independence National Historical Park, was designated a World Heritage Site in 1979.

Philadelphia, colloquially referred to as Philly, is the most populous city in the U.S. state of Pennsylvania. It is the sixth-most populous city in the United States with a population of 1.6 million at the 2020 census, while the Philadelphia metropolitan area with 6.33 million residents is the nation's ninth-largest metropolitan area. Philadelphia is known for its culture, cuisine, and history, maintaining contemporary influence in business and industry, culture, sports, and music.