What building hosted the 1787 Constitutional Convention and the signing of the U.S. Constitution?

Independence Hall hosted the 1787 Constitutional Convention and the signing of the U.S. Constitution.

The Philadelphia building was completed in 1753 as the Pennsylvania State House. Delegates met there during the Constitutional Convention from May through September 1787, debating how to replace the Articles of Confederation with a stronger federal framework.

The Constitution was signed in the building’s Assembly Room on September 17, 1787. Thirty-nine delegates signed the document, while several delegates who opposed or declined to support it did not sign.

The same building is closely associated with the Declaration of Independence, which the Second Continental Congress adopted there in 1776. That shared history is why Independence Hall is central to both the 1776 and 2026 national commemorations.