Fort Clark can refer to the following locations in the United States, listed alphabetically by state: Fort Clark Trading Post State Historic Site, North Dakota Fort Clark, later Clarksville, Indiana Fort Clark, built at 17th-century site of former Fort Crèvecoeur near Peoria, Illinois Fort Osage (Fort Clark, Missouri), site of the Treaty of Fort Clark, ceding Osage Nation lands Fort Clark, North Carolina, site of the Battle of Hatteras Inlet Batteries Fort Clark, Texas, near Brackettville, Texas