From the 1780s through the Civil War the landscape of Lincoln County would have been marked more by the iron industry than by any other activity than agriculture. Since the last firings of the towering stone furnace stacks in the 1880s, the physical legacy of the industry has slowly but inexorably faded from the terrain. Four iron furnace stacks, in varying states of disrepair, a few grand residences, and the overgrown remnants of spent ore and iron mines are all that remain of the once highly profitable and visible industry. The industry would have been visible not only through the permanent structures left on the land, many of which (particularly the iron forges and the innumerable dwellings which housed its slave laborers) are long gone, but also through the marks it made on the environment. Iron mines were dug into the "Big Ore Bank" which began a few miles northeast of Lincolnton. Beginning in the 1840s, lime for flux was dug in the same area of Lawson Keener's quarry. Probably the most visible and environmentally disruptive element of the industry, however, was it destruction of countless acres of virgin forest. To produce the immense amounts of charcoal required to fire the furnaces, which often ran day and night for months on end, thousands of cords of wood had to be cut. The smoke of the wide wood pits in which colliers laboriously transformed timber in-to charcoal would have overwhelmed even that rising from the nearby furnaces and forges. The most prominent extant remains of the industry, aside from the grand residences of Vesuvius Furnace, Ingleside and the Jacob Forney House built largely on its profits, are the four surviving furnace stacks. The Vesuvius Furnace stack, the oldest of the four and, if its alleged construction date of 1790 is accurate, the oldest documented structure in the county, has been reduced to a collapsed footing of stones. The other three stacks - Madison (ca 1809), Rehoboth (ca 1814) and Stonewall (ca 1862) - though tumbling in places as a result of more than a century of inactivity, clearly retain their basic configurations. Constructed of large cut stones, these tapered stacks rise like massive truncated obelisks to heights of more than thirty feet.

All furnaces are located at the foot of an embankment close by a stream. A bridge would have extended from the embankment to the open top of each stack, allowing the iron ore, lime flux and charcoal to be easily transported for dumping into the stack. Streams turned the water wheels which powered elaborate bellows arrangements. These bellows, often taking the form of huge cylinders, fed a continuous stream of air into the furnaces' fires. Tall, deep notches, cut into the bases of the stacks, provided access to their cores. Air from the bellows was led by a pipe through one of the notches into the firebrick or sandstone hearth of the furnace which held its molten ore. Another opening at the base, and possibly a second, provided a gap through which the molten iron was poured, probably directly on to molded sand floors at the bases of the stacks.

Their wheels, bridges and bellows long ago collapsed or were washed or carted away, but the Madison, Rehoboth and Stonewall furnace stacks still loom beside their streams and embankments as silent memorials to a once vital industry.