A few silver coins in a field near Rena turned into what researchers say is the largest Viking Age coin hoard ever found in Norway.

Rune Sætre and Vegard Sørlie found 19 silver coins on April 10 while searching a field near Rena, about 18 miles north of Elverum in southeastern Norway, according to the University of Oslo’s Museum of Cultural History. After the initial find, they contacted local officials, which led to a full archaeological investigation.

Researchers later recovered 2,970 silver coins. The museum estimated the hoard was likely buried around the year 1047.

Officials said the coins were minted between the 980s and 1040s and include the names of rulers, including Æthelred II, Otto III, Harald Hardrada and King Cnut. The museum called it “a coin hoard without parallel in a Norwegian context.”

Many of the coins were minted in England or Germany. The museum shows how strongly foreign currency shaped Norway’s economy late in the Viking Age.

Professor Svein Gullbekk said, “Foreign coinage dominates the circulation of money in Norway up until Harald Hardrada (1046–1066) established a national coinage.”

Archaeologists also think the hoard may be linked to the region’s iron trade. Jostein Bergstøl of the Museum of Cultural History said the area saw “enormous iron production” for centuries, with processed iron exported to Europe.

Hanna Geiran, director general of the Directorate for Cultural Heritage, said she could “hardly believe” the discovery and called it “a national and an international event.”

Innlandet County Authority archaeologist May-Tove Smiseth praised the two hobbyists for contacting authorities instead of removing the coins. “This is an exemplary case of how it should be done,” she said, adding that they followed the Directorate for Cultural Heritage’s guidelines “in full accordance.”

Researchers are still analysing and registering the coins, and the museum said the hoard will likely be studied for years to come.