If you are into iron, the confederacy ran I think 6 major iron furnaces during the war .. The smelter poured the melted iron into ingot shapes that were carved in granite. They are still there.
The furnaces were named after the commissioners daughters and family. They are Virginia parks now. I have camped at the one named Elizabeth Furnace,
I thrive on that kind of history. If I get over to Virginia those parks will be "must see" locations.
I numbs my mind that they could deal with that much weight at those temperatures. Casting a Columbiad cannon must have been a hoot, not to mention fitting it to a carriage.