Hiking through any abandoned “working landscape” in the Adirondacks you are likely to come across evidence of the people that were here before: a lilac bush deep in the forest, an old butternut tree, perhaps an odd patch of daylilies, and, of course, old cellar holes and stonewalls.

The old Danker Farm in Johnsburg is just such a place. It probably hasn’t been used for any real farming for almost a century now. Like most abandoned farms in the Adirondacks, its pastures and fields have grown up to a chaotic mixture of poplar, white pine, fir, maple, beech and white birch. And, like most old farmland, the property is littered with old stone foundations and crumbling stonewalls.

But on this particular property there is also a mysterious circular stone structure. It is built into a small hill, has an interior diameter measuring 11’ 2”, and a depth of 8’ or so. The stones seem to be primarily glacial till rather than something from a mine or shaped by man.. There is some evidence of very old poor-quality marble mortar between some of the stones. At the bottom there is a purposeful rounded hole blocked with loose stone on the exterior; this may be an old air vent or perhaps the top of a small door onto which has collapsed loose stones. An exploration of what seems to be the bottom of the circular stone formation has yielded no other clues. There is stone rubble at the bottom that may be from a collapsed section. Although it is likely the structure had a roof, so far there is no evidence of one.

One hundred forty feet to the SSW is a small well-constructed foundation measuring 20’ x 20’. It appears to have a “basement” entrance. It does not, however, appear to be the foundation of the farmhouse. An inspection of the 1876 Beers Warren County Atlas indicates the farmhouse and barn were most probably one thousand feet or more to the SE from the circular stone structure.

Four hundred or so feet SW of the site is what appears to be a small open ore pit. Given the propensity of iron ore in the Adirondacks it was thought that this might be a small iron ore mine, Testing of the stone left around this pit shows no indication of any magnetism. Current thinking is that it is of hornblende with garnet deposits rather than magnetite/iron ore. In any case, the mine is small and probably was quickly abandoned.

To the north of the circular stone structure, by about one hundred feet, is a spring that flows into a twenty-acre beaver meadow. The area around the structure today is a mixed forest.

The circular stone structure, the 20’ x 20’ stone foundation, the small open pit mine, and the site of the old farmhouse and barn may be from the same time period and related in use to each other, but they may also not be.

Inquiries among friends, the staff at the Adirondack Museum, NYS Historical Association Research Library and the Farmer’s Museum in Cooperstown as to the purpose of the circular stone structure has intrigued many and triggered much speculation, but no real answers.

Some folks initially speculated that the circular stone structure was a well or a springhouse. If so, it would be extraordinarily large for either use. Furthermore, the loose stone would not have retained water.

Others have thought it may be a dry well, although given the time it was probably built (think the era of outhouses) that is unlikely. Furthermore, the land is on a slope and appears naturally well drained.

Perhaps a stone silo for storing grain or silage? Then again, it is rather small for such a use, how would you get the grain or silage out of the bottom? And wouldn’t mice and other rodents gain access to the grain stored by crawling between the loose fitting stones? Insects, too? And grain would likely rot from the dampness and exposure to the rain and snow that would blow in. More importantly, why not just build a large wooden silo like everyone else did?

Some have wondered if it was used as a smoke house, but there is no evidence of a fire in the bottom of the structure or any damage to the rocks that might suggest a fire or high heat.

And some have thought maybe it was a place to store hanging meat. Breaking into the circular stonewall would certainly have proven a challenge to a hungry bear or passing mountain lion. The present owners of the property heard that years ago some folks used to age their venison in the “well”, climbing down into the structure on ladders, so perhaps that is the answer – or just some local humor. But if so, why aren’t such structures more common given that other early settlers would have similar needs? Would it not be more likely for this farm’s past inhabitants to hang butchered animals such as pork, mutton, beef, and venison for aging in a barn or well built shed like everyone else did?

Cold storage for cheeses or milk? But then why not build it adjacent to or at least closer to the farmhouse, or use the cellar of the farmhouse itself?

An ice house storing ice from the beaver pond? New England farmers have been know to build stone ice houses into the north side of a hill. Those structures, however, were typically built of stones tightly fitted and with a good door to access the ice as you needed it. The nearby beaver pond also would not likely generate good blocks of ice for such storage.

A re-reading of the excellent Stonewalls & Cellarholes: A Guide for Landowners on Historic Features and Landscapes in Vermont’s Forests (Robert Sanford, et al, 1995, pdf), makes me think it must have been some kind of kiln.

In a lime kiln successive layers of limestone with wood or coal were built up within the kiln and then a fire was started at its base which burned up through the materials in a controlled fashion. As the limestone was heated it turned to powder. Once the fire was out and the kiln cooled, the lime was raked out through the small hole in the base of the kiln. Today we think of lime as a primary ingredient in cement and mortars, but in the early agrarian societies lime was spread out over acid soils such as we have here in the Adirondacks and could increase crop productivity four fold. Although there is some rough marble formations at the base of Crane Mountain and a few marble ledges on the Danker farm, according to my geology-trained son Adam, the closest evidence of any real limestone formations are 40 miles away in Glens Falls.

Similarly, a charcoal kiln might be the answer. For perhaps a thousand years man has made charcoal by piling hardwood logs and branches and then topping the pile with earth. A fire would be lit at the base and the fire would slowly burn, limited by the oxygen from air that would seep in through controlled vent holes. Online research turned up a picture of such a charcoal kiln on East Mountain in Shaftsbury, Vt. But with no commercial iron smelting operations nearby, what was the demand for the charcoal? Possibly domestic use by residents?

Perhaps a forge for iron ore? Iron ore mining and smelting was big business in the Adirondacks years ago, even in the smaller settlements. But there is little evidence of iron ore nearby. Furthermore, smelting iron takes intense heat. Not only is there no evidence of that, but also to generate such heat one would need a high, small stack to maximize the air draft. That does not seem to be the design here.

But in the cases of all these kilns, there should be evidence of at least some lime residue, charcoal fragments or smelting residue. So far, none have been found.

This structure has many mystified. Mysterious stone structures appear all over New England and northern New York and have fascinated many. Christopher Pittman has done a nice job listing some on his website cellarwalls.com

After considering all the possibilities for this circular stone structure, some have suggested, in jest, that maybe it is a nest for an alien creature, Bigfoot’s home or a primitive missile silo…

So, what do YOU think it is and what was it used for?