The Old Exchange & Provost Dungeon is South Carolina's most historic building. Completed in 1771, the Exchange and Custom House was the economic, social and cultural center of the colony. South Carolina delegates to the First Continental Congress were elected here in 1774. The Declaration of Independence was presented to citizens from the steps. In addition, the U.S. Constitution was ratified in the Great Hall. President George Washington entertained here in 1791. The cellar was used as a Provost prison by the British during the Revolution. Pirates were imprisoned on this site in 1718.