Built between 1767 and 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. US Constitution ratified in the Great Hall. President 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. The Old Provost Exchange & Provost Dungeon is one of South Carolina's most historic building.