This small town was one of the original four or so French colonial towns founded in the region in the eighteenth-century. First established in 1722 on a tract of land granted by the Royal India Company to Pierre Duque Boisbriant—French commandant at Illinois and builder of Fort Chartres—the town derived its name from the rock cliffs against which it was sited—“Prairie by the Rock.” The town is home to many fine examples of French settlement-era vernacular architecture including the French colonial-style Creole House, built in a modified poteaux-sur-sol style, which hosts numerous public events throughout the year. The still-active town cemetery dates back to the eighteenth century, where one can find both worn gravestones and the old town well. The lively present-day town is tightly tucked between the US Army Corps of Engineers levees and the limestone bluffs—and offers a particularly compact area for exploring how these two features work to form the levee-protected zones.