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