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Melting Ice Reveals an Ancient Thriving Trade Route

High in the mountains of Norway, melting ice has led to the discovery of an ancient remote mountain pass, complete with trail markers and artifacts from the Roman Iron Age and the time of the Vikings. The remains reveal the dual historical function of this route: It was once a significant passageway for moving local livestock between grazing sites as well as for inter-regional travel and trade. This particular receding ice patch is known as Lendbreen. Because the ice in this patch is relatively immobile, hundreds of artifacts have been preserved in their pristine form; more rapidly-moving glaciers would have deformed them or obliterated them entirely. Most of these objects are from the Viking Age, providing a novel inland perspective which contrasts with age-old tales of the Vikings’ bold maritime travels.

Glaciers and ice patches throughout the world’s high mountain regions are receding, leaving behind precious remains, like Ötzi the ice man and his tool kit, that have been buried under ice for centuries. The rate of melt has been accelerating over the past few decades as a result of the warming climate. In the 1980s, glaciers lost less than a foot of ice per year, on average. That number increased every decade so that by 2018, glaciers around the world were losing mass at a pace of three feet per year. This rise in melt drastically propelled the field of glacier and ice patch archaeology — especially in Scandinavia, the Alps and North America — as archaeologists raced to collect artifacts uncovered by this process.

Earlier this year, Antiquity published an article about the ancient mountain pass uncovered on Lendbreen, which itself is a melting ice patch in the central mountain range of the Loomseggen Ridge in Norway. This retreating ice patch exposed lichen-free areas of bedrock where artifacts have been found simply lying on the bare ground. The dated artifacts indicate that the mountain pass was used from AD 300-1500, but suggest that its usage increased around AD 1000 during the Viking Age. This was a time of elevated travel, trade, and urbanization in Northern Europe.

The authors theorize that people began using the mountain pass in AD 300 (during the Roman Iron Age), when summer farming became more common in high elevations. “There might be many reasons why farming moved up the mountainside,” said Mark Aldenderfer, a distinguished professor of anthropology at the University of California Merced. His archeological research is focused on the high altitude cultural, genetic, and biological adaptations required to live permanently above 2,500 meters. He noted that this study is an excellent example of ice patch archaeology. The artifacts shed light on the functioning of ancient agricultural societies.

When the climate warms, even slightly, new lands become available for exploitation as the ground thaws. “Land exhaustion in the lower valleys may have led farmers to seek new lands—but much depends on the nature of the cropping systems and the availability of fertilizers,” he said. Even if lands weren’t completely useful for growing human food, they could still be used as pasturelands and for growing hay and fodder for cattle. This led to increased transhumance: the practice of moving livestock from a lower elevation grazing ground in the winter to a higher elevation grazing ground in the summer.

At the end of the summer season, fodder could be transported from high-elevation summer farms to downhill settlements. In this way, it would continue to nourish horses and cattle when snow covered the mountainsides. Fragments of leaf fodder and wooden implements, known as tongs, were among the artifacts found at Lendbreen that were associated with the transportation of fodder. They were radiocarbon dated to AD 264-533.

Upper left: an object interpreted as a tong (a clamp for holding fodder on a sled or wagon), dated to the Late Roman Iron Age; right: a similar, undated object, also from the pass area; lower left: a historical example from Uppigard Garmo, pre-dating c. 1950. Source: Glacier Archaeology Program & R. Marstein/Lars Pilø et al.

“These systems of land use are common in much of the world’s mountainous places… people do this in Tibet and the Himalayas all the time,” Aldenderfer added. “It would be interesting to see what kind of plants might be evidenced in the ice in order to see what was actually being planted.” In the Himalayas, for instance, there are many varieties of barley that are cold-adapted and can form seeds much faster than other types of barley in the world.

As the research period progresses, historical records indicate that long-distance travel and trade became more common in the region. The authors comment that, in Lendbreen, the fact that “the dates cluster in the Viking Age, particularly around AD 1000, is unlikely to be coincidental as it was a time of high mobility, emerging urbanism and increasing political centralisation in Scandinavia, and a period in which markets around the Irish, North and Baltic Seas were growing.” This was a time when the societal demand for mountain products — such as pelts and reindeer antlers for making combs — rose and motivated both local and long-distance travel, consequently elevating both inter- and intra-regional communication and exchange.

The findings on Lendbreen are varied and contain numerous types of transportation-related items including the remains of sleds, walking sticks, horse snowshoes, and horse bones. They also contain many everyday items, including a woven tunic and a mitten, textile rags, and a number of shoes made from hide. Most notably, archaeologists found ruins of a stone shelter near the top of the ice patch, indicating that this was a significant travel route.

A goat or lamb bit. Source: Glacier Archaeology Program & J. Wildhagen/Lars Pilø et al.

Horse-related artifacts are indicative of the actual path of the main route. Iron horseshoes are less likely to have been moved due to winds or other natural causes because of their weight. They also lie near the cairns that were erected to mark the path. Lighter objects off the main path may reflect alternative hunting routes up the mountain or may simply reflect the way these objects were deposited by wind or glacial meltwater movement.

Horses are an important area of study for archaeologists because they were the main source of transportation for many ancient peoples. Herders have selected them for a variety of characteristics, creating new distinctive breeds throughout history. “Horse DNA is a big deal,” said Aldenderfer. “In Europe, for the time frame of this particular study, it could be a situation in which somebody might say, ‘Well, let’s compare, maybe these horses did come from a breed from high-elevations or cold-adapted climates,’” so this could be something for future research to expand upon.

Historically, local people utilized glaciers for travel in the spring and early summer when the snowpack was deep enough to support packhorses and when the weather was not as brutal as during winter months. However, some stretches of the Lendbreen route contain very difficult terrain that would have been impossible to cross with packhorses in the absence of snow cover. The authors suggest that increased presence or absence of artifacts in certain centuries may reflect episodic patterns of alternative warming and freezing events. “Indeed, the glacier curves for the region show multiple expansions and contractions of high-elevation ice over the chronology of Lendbreen’s use for hunting and as a mountain pass.”

According to the authors, the late- and post-medieval decline in human activity on this mountain pass likely reflects the onset of the Little Ice Age in 1300 and the appearance of the bubonic plague that reached Norway in 1348; these two events are associated with to climatic deterioration, famine and depopulation across Europe.

Archaeological research at the Lendbreen ice patch first became alluring in 2011, when reports revealed that a sheep wool tunic from the third or fourth century was found near the ice. The authors hypothesize that this garment may have been cast off by someone in the “irrational throes of hypothermia,” as The New York Times put it. Since then nearly 800 artifacts, 150 bones and antlers, and over 100 cairns (human-made stacks of stones that served as trail markers) have been discovered by Oppland County’s Glacier Archaeology Program.

Reconstruction of the Lendbreen tunic, found in Oppland, Norway on August 4th, 2011.

Ice patches preserve ancient treasures better than glaciers — they are the best for this kind of archaeological work because they are usually less active and less dynamic than glaciers, and therefore lead to better artifact preservation. “Ice simply buries material, creates conditions for long-term preservation, and generally keeps it intact. As the ice melts, artifacts might be moved, but not terribly far,” Aldenderfer said. “But glaciers, man, they can be really rough. They pick stuff up, they move it up, they move it down, they crush it… the wave that glaciers bring is hard on artifacts.”

Lendbreen is the only known mountain pass that traverses an ice patch, preserving artifacts lost by those past travelers in exceptionally pristine condition. Consequently, archaeologists were able to decipher that the mountain pass served a dual function historically: In addition to facilitating inter-regional travel trade, the route also allowed seasonal transhumance between lower-elevation settlements and higher-elevation summer farms on which livestock was grazed. Before its whereabouts were lost beneath the ice, this route was central to Norway’s ancient mountain itineraries.

Archaeologists traversing the Lendbreen ice patch. Source: Klimapark2469/YouTube
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Mats Cuda
Mats Cuda
3 years ago

The melting ice reveals artifacts just lying there on the ground, which have not been destroyed or affected by the glacial melt – evidence that at one point there was no ice there. So why hasn’t anyone, at least to my knowledge, brought forth this fact to suggest as prima facie evidence that the current melting of the world’s glaciers is part of a cyclical pattern? Why is it nature’s fault that mankind has built cities on land that is but only some inches above sea-level when natural forces act to reclaim what is naturally theirs? surely someone will continue the thesis of the speed at which the ice is melting to which I will rebut how about the speed at which it froze? The artifacts are just lying there, which suggests a quick rate of global freezing – the opposite as we are experiencing now.

Reply to  Mats Cuda
3 years ago

I agree to this. A stone shelter would not likely remain standing if it was built on ice. It’s very presence is solid evidence of a warmer ice free climate in the past when the structure was built. This is not rocket science.

Reply to  Mats Cuda
2 years ago

>>to suggest as prima facie evidence that the current melting of the world’s glaciers is part of a cyclical pattern?

Not exactly. These are maritime mountain glaciers. Maritime areas with high precipitation are well known to have more erratic profiles in different eras. Also well know was the Little Ice Age and that around 6,000 years a high global temperature.

For example in Alaska there still are a few glaciers which are expanding in length. Not many, but a few.

Norway has a maritime climate. So does southern Greenland.

I, too, have misgivings of the political use of climate change. However, this is not a good example of such misgivings. Also of note is Otzi, which he fell dying or dead in an Italian/Austrian border region ice field that later grew and remained covered for over 5,000 years.

Jerry Ray
Jerry Ray
3 years ago

So much for fossil fuels causing climate change .The evidence shows it was much warmer in the past with no fossil fuels.So why are clueless politicians spending trillions trying to change it. We’ve already cleaned it up.

Reply to  Jerry Ray
3 months ago

I recognize this is an old comment but i come with new knowledge. It’s not all about burning fossil fuels Jerry. Our contribution to CO2 in the atmosphere has offset and over corrected for what is supposed to be the next ice-age. If it was up to the planet, we would be headed into a new ice-age and instead we have pumped enough GHG’s into the atmosphere to insolate the planet and drive us to a warm, disease spreading, flood, and storm surge environment where species are dying and land is sinking. you are clueless for thinking we have cleaned anything up when we’ve only continued to make it worse since before the 80’s. problematic thinking Jerry.

1 year ago

Your online accounts of this unprecedented phenomenon are a priceless contribution to humanity. The whole world could never thank you enough.
Old Retired Professional Archaeologist
(ORPA! Oh well.)