You would be quite forgiven for seeing a fortress upon first glance at this photo. That would certainly have been my first thought had I not known that I was heading to a 19th century iron furnace. One of several small smelting operations that sprung up in the late 18th and early 19th century, this one was the one of a pair that used charcoal as a fuel. I have seen iron furnaces before, and I find them fascinating, but I can't recall any others having such a fort-like appearance. It is interesting to wonder if it was a aesthetics choice or a practical one.
Points of interest
Clove Furnace is the historical site that is the subject of this story.