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