Little Rock is the capital and most populous city of the U.S. state of Arkansas. It is also the county seat of Pulaski County. It was incorporated on November 7, 1831, on the south bank of the Arkansas River close to the state's geographic center. The city derives its name from a rock formation along the river, named "la petite roche" by the French explorer Jean-Baptiste Bénard de la Harpe in the 1720s. The capital of the Arkansas Territory was moved to Little Rock from Arkansas Post in 1821. The city's population was 193,524 at the 2010 census. The six county Little Rock-North Little Rock-Conway, AR Metropolitan Statistical Area (MSA) is ranked 75th in terms of population in the United States with 724,385 residents according to the 2013 estimate by the United States Census Bureau.