The USS Cairo was one of seven identical city class ironclads. What happened to the other six?
The USS Cairo and USS St. Louis (renamed the USS Baron De Kalb) were sunk by torpedoes on the Yazoo River (Cairo in 1862; Baron De Kalb in 1863). Only the Cairo was salvaged 102 years later. The USS Cincinnati was sunk twice during the war – once at Vicksburg – and raised and re-fitted to survive till the end of the conflict. It was then sold and sank at its moorings on the Cache River in 1866. The USS Carondelet and USS Mound City were sold after the war, and broken up for scrap. The USS Louisville and USS Pittsburg were sold in 1865, with the Pittsburg being abandoned in 1870.