In our conversation this week, America Unearthed star Scott Wolter asked me to explain to him what I thought of the so-called “mooring stones,” medium- to large-sized rocks in which are found small, round holes obviously carved by iron chisels. Hjalmar R. Holland, one of the early advocates of the Kensington Rune Stone, first claimed in 1907 that these rocks were mooring stones used by Vikings to anchor their longboats along the edge of a vanished Minnesota lake.
This hypothesis was effectively debunked in 1981, when a team of Minnesota archaeologists surveyed the mooring stones and found no correlation between their placement and any water routes, current or former. Wolter agrees that the mooring stones have nothing to do with boats, and he challenged me to explain them. I told him that I had no idea what they were and wasn’t familiar with them. (Yes, it’s true: I don’t know everything, and I’m happy to admit it. It’s humbling to consider how much there always is still to learn.) One of my many correspondents helped me out with this “mystery” by directing me to the Fall 1998 edition of Minnesota History where Tom Trow explained these artifacts in a clear, concise, and effective manner.
In the article, Trow discusses how he and a team from the Minnesota State Archaeological Survey tried to determine the origin of the stones. First, they tried to test the hypothesis that these were mooring stones. As mentioned above, this hypothesis failed when the stones turned up in places boats could never have traveled and—crucially—are not found in documented Viking sites in Greenland and Newfoundland, indicating that such stones were not used anywhere else along the proposed route from Norway to Minnesota.
Next, the team tried to test another hypothesis, that the holes were the result of nineteenth century stone-blasting techniques. In that period, large stones were cleared from farm fields by drilling a small hole, filling it with blasting powder, and then exploding the stone. To make a very long investigation somewhat shorter, the team found an elderly farmer named Emil Mattson who participated in such blasting practices in the early 1900s and was able to lead the team to a failed rock blast from that era. This stone had the tell-tale drilled hole, but also had radial blast lines where the blasting powder had exploded. Unfortunately, the cleaved rock was too heavy to move, so both parts, along with the halves of the hole, remained in place. The team used the marks on the rock to identify similar markings on the foundation stones of old barns and houses to demonstrate that such buildings were constructed from rocks blasted in this way.
The mystery of the small holes in many large rocks left on the landscape can be easily explained: the ones we find today are simply those that were left unblasted, either forgotten or intentionally passed over. “They didn’t get around to blasting those,” as Mattson said. The so-called mooring stones are, in fact, recent historic artifacts, no older than the beginning of nineteenth-century farming in the region.
At top below is a “mooring stone,” and on the bottom is Trow’s photograph of one that was left in situ after being blasted. You can see the clear similarities.
So, again: The obvious conclusion was that the “mooring stones” were simply rocks that were prepared for blasting and—for whatever reason—were abandoned before being blasted. The fact that rocks at every stage of preparation, from initial drilling to blasting to use in construction, could be seen and documented made this the most likely solution and the one best supported by evidence.
“Why,” Scott Wolter asks, “do the archaeologists I’ve discussed this with dismiss this thesis and insist they were made for blasting the rocks when the physical evidence refutes this?” As we’ve seen, the “physical evidence” coupled with the testimony of someone who was actually involved in chiseling these holes is rather unambiguous on this point. The reason the stones Wolter examined show no signs of blasting is because they were the ones that weren’t blasted. The existence of stones that were blasted seems to be eloquent testimony to the holes’ purpose.
That said, technically speaking, the team’s findings apply only to the handful of stones they studied, so it is theoretically possible that other mooring stones had different origins. However, given the clear and direct evidence of their origin and use, I’m comfortable generalizing that most if not all of these stones are the remains of nineteenth century land-clearing techniques.
1/30/2013 01:08:40 pm
1/30/2013 10:25:02 pm
I take your point, but if I did that then Google users wouldn't find my post when searching for them. I did, however, make plain these were only "allegedly" mooring stones.
7/24/2018 11:26:27 pm
I have heard of the 'Viking Trail' in Minnesota. If anyone knows of a map containing the locations of stone holes or other Viking artifacts, please allow readers to know an IP address to the map or a book title containing such. I have only seen altar rock and have been in the Alexandria museum as a child.
11/24/2020 11:55:47 am
I do not know if you are still interested in what the Vikings did in 1362. I have a story written about the Kensington Runestone and about the park that is built around the site. It disturbs me that so many people say this is just untrue. Please contact me if you are still interested.
Bryon Van Horn
2/6/2013 10:35:56 am
"Stone holes" come from many sources i believe. Blasting, mooring and property marking to name a few. There is to much evidence for each category to simply say all stone holes are due to just one activity.
6/8/2013 03:04:27 am
I have found several triangular holes near where I live on the midcoast of Maine. The three parts of each hole are rounded. I believe others here have been re-used w iron pins and rings. They look identical to the ones on Follins Pond on Cape Cod. I found a star chisel which equates to round holes. Flat head chisels make triangular ones. Since the star chisel is more "sophisticated," I speculate triangular holes are older.
4/5/2016 10:20:56 am
I was a member of the archaeological team, and with Tom Trow in 1981 when we interviewed the elderly Emil Mattson on his farm near Kensington, MN. He made it very clear, from his own participation in chiseling the holes in the stone, that, at least for the stones around Kensington in Douglas County, Minnesota, the holes were the result of blasting practices by farmers in the late 19th century.
4/28/2016 11:26:15 pm
the viking mooring stones holes i believe could be blast holes when the vikings needed stones to make tools.
9/2/2016 04:20:54 pm
It seems like an awfully complex way of anchoring a boat. Why not beach the boat or tie a rope to a tree?
9/2/2016 11:03:58 pm
I found several of these rounded triagular holes (of various sizes) in large foundation stones that were built in preparation for the first railroad station here in 1850. They are of various sizes. They were not used for blasting here - rather a method of lifting and stacking into place. However, I found a cast iron fence that (in 1860) used triangular holes to anchore the fence into supporting curb stones - dozens of these; and all the same size. - The railroad standardized just about everything including these "mooring holes." It seems the star or cross chisel (which made round holes) was preferred by the RR after 1860. So the "moooring holes" served several functions here but these triangular rounded holes must have been more difficult to make when compared to the cross chisel (which is essentially two chisels made into one). I will show these on youtube in a couple of weeks. --
3/11/2017 06:16:21 pm
David, I would love to know more about your response, and also what area of the country you are referring too as MN holes seem to be out west around the 45th latitude. A friend just discovered one that is also triangular on a creek at the 45th latitude, but it is not out west which is strange to me. So I am again reseaching a common sense explanation and history of quarry or blast holes and would love to hear and see your video. Regards, Scott
3/11/2017 06:41:09 pm
Hey Jason, long time, hope you are well. I would like to add the holes found in MN and considered to be "Mooring" holes by some, do not look like the triangular ones shown in the pictures above, but are more petaloid in structure and not machine like perfect. Although it needs more research, I do believe the Expedition may have made some, but not as mooring holes per sae, but as markers for those yet to come and configured strategically for an ancient form of today's GPS when combined with a geometric formula. In my mind, that formula and method would be an incredible logistics advantage for supplies and communication, so important that it could have been kept secret and eventually misunderstood as the Holy Grail..Not that I have a vivid imagination or anything, lol..
David A Korth
10/23/2019 08:17:00 pm
What makes you all think that the shore lines were the same now as they were a thousand years ago? They found a stone on my Grandparents farm in northern Iowa decades ago. My great Grandparents settled in north Iowa in the 1800s. My brother found one hunting. My mother told me people from the state came and took the one found on her parents farm. How far did the great lakes stretch down a thousand years ago? People assume the terrain was the same now as it was a thousand years ago. I had a book about these theories but ofcourse I can't find it and I don't see it on Amazon. Supposedly there are remains of a viking ship that runs under the highway going through Elma, Iowa. Unfortunately the author of the book I had was not a professional archeologist so his discoveries were discounted by the professionals.
11/24/2020 12:04:51 pm
There was an extension of Hudson Bay that extended almost to the Iowa border. This is how the Vikings were able to sail their ships all the way from Scandinavia to central Minnesota. Its a given that prehistoric Lake Agassiz covered North Dakota and western Minnesota 10,000 years ago. That would have made west central Minnesota a salt water sea with the many hills, such as Inspiration Peak, Andes Tower Hills and the hills north of Kensington....islands.
Gerald L Kirstein
4/8/2022 07:51:39 am
I have been surprised at the continued resistance to the Kensington Runestone as being genuine. It certainly must be genuine. The keys to determining the validity that the Vikings were indeed there in central/west Minnesota are: 1) the fact that king Magnis of Norway commissioned an expedition to Vinland in 1354 and 2), the reference made in the two messages on the stone as to their location, namely, their original camp, where the massacre happened, was "one day's journey north" from the island and their ships being "14 days" north from the stone and their 'island.' The later discovery of Cormorant Lake, the two possible islands that might have once existed there, and the finding of an ax blade at the site ought to be proof enough of it being genuine, particularly in the context of nautical distance in Viking terms. No one who wished to fake this stone could ever have known about the travel distances related to this group of explorers, i.e., that one day's journey was equal to 75 miles and 14 day's journeys would place them at the south end of Hudson Bay. In order for the stone to be fake one would have had to understand Viking runes and how to write them, create the narrative, haul a 200-pound rock to somewhere in the general area of uninhabited land where no one was living and plant it (a fake runestone would have had to be planted approximately 38 years before the Swedish farmer's son unearthed it clutched in the roots of a tree). A careful processing of the material evidence eliminates the possibility of fraud when everything is looked at from King Magnis' declaration in 1354 and the group of Vikings headed by Paul Knutson, although there is no proof that Paul Knutson and his group ever made it there. The doubters stand on this 'lack of evidence' and technical disagreements about certain vowels and inscriptions made on the stone which could not be confirmed until just recently (in favor of authenticity). Subsequent stories about a group of Indians being encountered with blonde hair and blue eyes in North Dakota seems quite possible given its proximity to the stone even though the tribe died from smallpox before they could be investigated and verified. I'll be at the museum and farm in late May for another visit. I think they should make a movie about it.
5/17/2022 08:05:07 am
The book Westward from Vinland makes references to the Kensington Stone with pictures and translations, the lives of the blond Mandan Indians, Viking implements discovered in Minnesota, a Viking grave site near Lake Nipigon, Mooring stones, Weather that was much warmer as Vikings were farming in Greenland and their source of timber for building was Newfoundland since it was much closer than Norway. I'm certain there are more facts in the book I have forgotten as it has been years since I read it. Since reading the book and researching other information regarding Vikings in North America I have no doubt of their existence in Central and Eastern North America.
5/29/2022 01:26:22 pm
Grew up looking at the rock hole at the end of a peninsula East Lake Latoka. It was about 5 ' above the water in the 50's. I was also aware of an underwater rock wall which I just learned was part of a fish hatchery in the 20's or 30's. The wall appeared to be 3 to 7 feet under water and was along the North shore just North of the peninsula rock and must have been part of enclosing that NE shallow bay / fish hatchery. Now I understand the peninsula rock was broken off in recent times for a Runestone Museum prop. Since the water must have been much lower back then, then that peninsula rock would have been way above the water, maybe 10 to 15 feet. Now that the mooring hole theory has morphed into the blasting hole theory might that rock have been targeted for use in the stone dam to contain the fish hatchery? Regardless of water height that position seems unlikely to have been of use to farming / clearing. I also noted in reading about the unused blasting holes that a fan shape surrounded the hole and I believe that stone had one. However the water was hypothesized to have been deeper, not shallower, in 1362 and since that rock was not an impediment to farming, I would like to know the current best guess as to the hole. Incientally I swam across lake Latoka from Firemen's lodge to the point where the bass fishing was excelent and I love fishing from show in the shallow NW bay and swimming at the beach where a small stream ran into Lake Cowdry. :)
5/29/2022 01:33:29 pm
Another note on my 1950's observations of NE Lake Latoka. Not knowing about the fish hatchery until today I speculated that the underwater wall was a sort of fish trap set up on a shallower lake Latoka by original inhabitants. Turns out it was indeed a sort of fish trap but done as a fish hatchery in the 30's...I grew up a couple miles away in Jacobson's Addition on Willow Drive and Meadowlark Lane.
12/3/2022 07:31:46 pm
Have the stone holes been examined for microscopic metal residue and those metal shavings analyzed or dated? That type of analysis could determine if the holes were created by a 14th century chisel or a 19th century one.
12/5/2022 01:48:32 pm
Don’t know if holes tested for metal or blast residue and evidence seems likely they were blast holes. Drilling a difficult hole to anchor a boat seems silly in relatively calm water. Having said that the lake latoka hole was at the end of a long narrow peninsula by deep water where it made no sense to remove as there were no farming activities. If one wanted to build a cabin the stone was in no way a problem. This leads me to what ive observed near Seattle and that is any giant tree cthat could be cut down was cut down in spite of any ability to recover it and many fallen giants remain today. Since the Latoka stone was the biggest I’d ever seen in the area maybe it was just practice since boys will be boys.
12/5/2022 03:25:27 pm
Thanks, Jim. I’ve never been convinced the purpose of the holes to be for “mooring”, as it seems implausible. If explorers from Iceland made it so far inland, and I think there is evidence for that, perhaps they placed staffs in the holes to help with portage navigation, or even the “land claim” theory that Scott described; as commercially repulsive and academically void as his “notions” may be.
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I am an author and researcher focusing on pop culture, science, and history. Bylines: New Republic, Esquire, Slate, etc. There's more about me in the About Jason tab.
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