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