
Built in 1740, the Cahokia Courthouse is the oldest courthouse in Illinois and the only remaining courthouse from the Illinois’ territory. It is an example of French Colonial vertical log construction (poteaux-sur-solle). Lewis & Clark used the courthouse for collecting information and supplies leading up to the Corps of Discover Expedition. The structure was moved to St. Louis for the World’s Fair in 1904 and Chicago in 1906, before being rebuilt on its original site in 1939.