Argosy Casino Sioux City was a riverboat casino located on the Missouri River in Sioux City, Iowa. Directions. Argosy Casino, Sioux City, IA. Reviews from Argosy Casino employees about Argosy Casino culture, salaries, benefits, work-life balance, management, job security, and more. 28 likes · were here. Court St. Sioux City, IA () Also at this address. Don't plan a trip to Sioux City with the idea you will gamble at the Argosy. Larsen Park Rd Sioux City IA USA ; Telephone. The former Argosy Sioux City casino has been sold to an Illinois firm that hopes to move the riverboat down the Missouri River as early as next. . The former Argosy riverboat casino has pulled away from its dock in Sioux City and started its journey to a shipyard in Illinois. Argosy Casino Sioux City Website ; Casino. It was an abrupt end to an operation that began in when the Argosy opened on Sioux City's riverfront to great fanfare. Landmark & Historical Place. Argosy Casino. It was a riverboat casino that has been closed for quite a while. You can't even. () More. Argosy Casino Sioux City ; Address. +1 () ; Website. It was owned by Penn National Gaming. Advertisement. Previously, the.