A photograph that for three decades posed a Civil War mystery appears to be a long-surviving hoax.

The photograph of what appeared to be a far older photo — showing a figure in a coat and hat and the blurred image of a warship — surfaced in 1986. Some historians believed it might be a photo of the CSS Georgia, a Confederate ironclad that sank 150 years ago in Georgia as Union troops captured Savannah.

The man who photographed the picture, John Potter, initially said he found it at a yard sale but couldn't afford to buy it. Now Potter tells The Associated Press the photo is a fake he made as a teenager using a 2-foot model of the ship and his brother in costume standing in a marsh.