The United States Constitution was signed in Independence Hall.
The building was known in the 18th century as the Pennsylvania State House. It stands in Philadelphia and is the place where the Second Continental Congress adopted the Declaration of Independence in 1776 and where the Constitutional Convention signed the Constitution in 1787.
The Constitution was signed on September 17, 1787, by 39 delegates. The convention had met in the building from May through September to replace the Articles of Confederation with a stronger federal framework. George Washington presided over the convention, while Benjamin Franklin was among the delegates who supported the final document.
Independence Hall is therefore connected to both major founding milestones, but they occurred eleven years apart. The building’s earlier name can create confusion in trivia questions: “Pennsylvania State House” is historically accurate, while “Independence Hall” is the modern name and the accepted answer here.