NEW YORK, NY.- It was December and the first snow of the season was falling when the three friends set out on their weekly hunt through the fields of Ostfold, in southeastern Norway. Although it was not quite 6 p.m., the sun had set hours earlier and, except for the flickering glow from their homemade flashlights (aka bike lights duct-taped to sticks), it was pitch black.

Tromping across the blanketed farmland, the men came to a low outcrop of rock, a few feet wide. With a child-size plastic broom, they brushed away the newly fallen snow from the stone to reveal the outline of a ship, its curved keel carved into the granite roughly 3,000 years ago.

It was just one of more than 600 Bronze Age rock carvings, known as petroglyphs, that Magnus Tangen, Lars Ole Klavestad and Tormod Fjeld have discovered. Since making petroglyph hunting their collective hobby, in 2016, the three enthusiasts have transformed knowledge about prehistoric art in Norway, more than doubling the number of carvings known in their home region. And although they are motivated, in part, by the pleasures of friendship and the outdoors, their findings have also lent serious weight to theories about the mysterious petroglyphs’ meaning.

Rock carvings from the Bronze Age (which in Scandinavia began around 2000 B.C.) are common in parts of Sweden and Norway. Regions in both countries have been declared UNESCO heritage sites because of the density and the diversity of the images, which include human figures, animals, geometric shapes and, frequently, ships. Yet because they are commonly cut into granite that is low to the ground and easily obscured by leaves or snow, they often go unnoticed.

Petroglyphs are also easier to see when the sun is not overhead — a realization that has been one of the keys to the three friends’ success. Because the hunt for them is a hobby rather than a career — Tangen is an archaeologist working in a different field, Fjeld a graphic designer, and Klavestad a landscape architect and artist — they make time for it at night.

“This is not an 8-to-4 job,” said Tangen. “It has to be a passion.”

The thrill of the hunt has naturally led them to speculate on the carvings’ meaning. Because the petroglyphs tend to be more visible in the slanted rays of dusk, or with angled artificial lights, Tangen said he believed that their creators had made deliberate use of shadow and light in their work. Thanks to the sun’s changing angle, petroglyphs can look different depending on the hour of the day, or season, he explained. “I think the images have to do with the awakening of people’s minds to time,” he said.

That is in keeping with findings from professional archaeologists about rock art and stone monuments, in places like British Columbia and Scotland, whose features are visible only at certain times of year. There is also evidence for another one of Tangen’s theories: that some of the images were meant to be seen in flickering light, so that they appeared almost animated.

Kristin Armstrong-Oma, a professor of archaeology at the University of Stavanger, said that “in excavations around some carvings, archaeologists have found signs of burning or charcoal.” That suggested fire was being used, almost like a movie camera. “The living flames give the carvings a feeling of movement,” she said.

The petroglyph-hunting trio got their start in 2016, when Fjeld, the graphic designer, was walking his dog in the countryside and found a strange mark in a rock. He wondered if it was made by humans or nature. Trying to identify it online, he came across a website with photos of petroglyphs, and contacted its owner, Tangen, who suggested Fjeld’s find could be a Bronze Age cup mark — a simple, round carving that is a common motif in prehistoric art.

His interest piqued, Fjeld started paying better attention on his walks, and soon found a carving that was unmistakably made by human hands: an image of a ship.

“That was very, very fun,” Fjeld said. “So I started going on a regular basis.”

Tangen, who had made similar discoveries while walking his own dog, joined him, and before long suggested that they invite Klavestad, a local enthusiast who had found his first carving when he was 10.




“We didn’t know each other, but I hadn’t met anyone else with so much passion for it,” said Klavestad. “We are, all three, very dedicated.”

Since then, the three have gone out roughly one night a week, and it’s not unusual for them to come home at 2 or 3 in the morning.

“Yes, our families think we are crazy,” said Fjeld.

Because so much Bronze Age rock art was made near the sea, the trio begin by consulting topographical maps to see where the sea level, which was higher in the Bronze Age, would have been 3,000 years ago. Aerial photography has also helped them identify areas with the low granite outcroppings that Bronze Age artists appear to have favored.

Norwegian conservation laws prohibit the petroglyph hunters from digging, so they work only with the most rudimentary tools: flashlights and brooms. “It’s important that we are not one, but three,” said Klavestad. “That way one can hold the light, one can sweep and one can look. You discover more that way than if you are alone.”

Although archaeologists have long maintained that the carvings are primarily mythological or ritualistic, that notion is changing. “All the myths we create, all the symbols we make are always rooted in something real; they represent fragments of the past,” said Armstrong-Oma, the archaeology professor. “These are extraordinary because they allow us to see the world the way that Bronze Age people saw it.”

In addition to carvings of humans, animals and ships, Fjeld, Klavestad and Tangen have found several panels with pairs of life-size footprints. Jan Magne Gjerde, senior researcher at the Norwegian Institute for Cultural Heritage Research, said the footprints had been “linked to a death ritual that symbolizes walking your final walk.” But, he added: “That’s just an interpretation.”

The guys prefer to interpret them as a sign that their Bronze Age ancestors trod the same ground. “It just gives you the idea that maybe they came over the ridge and were just looking at the sunset,” said Tangen. “When we found this it was like, ‘Yes, they have been here!’ ”

Whenever the men discover a new carving — last year, they found around 80 — they photograph it and report it to Norway’s cultural heritage office. It is then the job of Jone Kile-Vesik, an archaeologist, to verify the find. (“It’s usually quite easy to tell if they are real or not,” Kile-Vesik said. “Because they would have been made with stone tools, which give a softer cut than metal ones.”)

If the panel looks authentic, Kile-Vesik then registers it into a national database for cultural preservation. Although there had been a few “differences of opinion,” she said, most of the three men’s discoveries have been validated, and they have put Ostfold on the map as a significant locus for Bronze Age culture.

Fjeld, Klavestad and Tangen all said they were pleased to play a role in preserving their region’s heritage. But they were also just in it for the fun of hanging out together in nature. At one point on that December night, they reached a particularly large rock outcropping and swept aside the quickly accumulating snow to reveal an earlier discovery: a spectacular carving of human figures with outstretched arms above a boat.

“We call it the ghost carving,” Tangen explained as Klavestad poured from a thermos of mulled wine. “Because it seems like they’re hovering or dancing over the ship.” He warmed his hands on the cup.

“I love that you can be driving through the landscape and have this map in your mind,” he said: “a gallery of all the ships and footprints and people dancing. It gives you so much joy.”

This article originally appeared in The New York Times.