Indianapolis /ˌɪndiəˈnæpɵlɨs/ (abbreviated Indy /ˈɪndi/) is the capital and most populous city of the U.S. state of Indiana, and also the county seat of Marion County. In 2013, the city's estimated population according to the U.S. Census Bureau was 843,393, making it the 12th largest city in the U.S.