A throng of more than 6,000 amateur researchers from the heritage organization Erfgoed Gezoeken have spent the last several years examining imagery of the hills, dunes, valleys and forests of the central Netherlands, in search of archaeological and historical anomalies. The efforts of these citizen scientists to uncover more information about the ancient past hit the proverbial mother lode, as the amateur archaeologists discovered the remains of approximately 1,000 prehistoric burial mounds, distributed far and wide across the country’s interior rural landscape.
Citizen Scientist Strategy Meets Success
Under the auspices of the Erfgoed Gezoeken’s Heritage Wanted project, the citizen researchers concentrated their efforts in an area that includes plenty of unspoiled land, in and around a pair of national parks known as Veluwe and Utrechtse Heuvelrug. A few mounds had already been found in this region, leading the amateur enthusiasts to believe that many more of these astonishing landmarks were out there somewhere, just waiting to be discovered.
Citizen scientists in action checking a possible mound site. (© Heritage Gelderland )
This assumption proved to be correct, to an extent that has shocked the archaeological community in the Netherlands. The burial mounds , which come in a variety of sizes, were used to bury the dead in the Bronze Age (3,200 to 1,200 BC) and to some extent during the Iron Age (1,200 to 600 BC) as well. Many sacred rituals would have been performed in association with the burials, just as they were in all the places around the world where these elaborate and impressive mounds have been found.
Netherlands’ Ancient Mound-Building Culture is Revealed—and They Were Busy!
The Erfgoed Gezoeken organization is sponsored by the University of Leiden and several cultural heritage groups active in the central Netherlands.
In total about 6,500 people volunteered to play the role of citizen scientist for this particular project, and this teeming horde of eager sleuths spent thousands of hours poring over the details of high-resolution aerial images of the Dutch countryside looking for evidence of ancient civilizations .
Primarily, they were searching for irregularities in the contours of the landscape that might suggest the presence of a burial mound or tomb. Through this method the citizen scientists identified more than 1,000 raised areas that they felt could possibly be burial mounds.
One of the images showing potential burial mounds found by a citizen scientist. ( © Heritage Gelderland )
“We have found so much more than we expected a few years ago, and that is really down to so many people coming forward to help, so we could cover a far larger area,” University of Leiden archaeologist and project organizer Eva Kaptijn told the Dutch News .
The discovery of the burial mounds has generated the most publicity. But the amateur searchers also identified nearly 15 square miles (38 square kilometers) of ancient agricultural fields, along with about 900 sites where charcoal may have been produced thousands of years ago.
“The Veluwe and Utrechtse Heuvelrug are now nature reserves where you walk through the heather fields and woods, but in the in the Iron Age, 1,000 BC, it was one enormous agricultural area,” Kaptijn explained. “So you look at the landscape in a completely different way.”
So far, fieldwork has been carried out at 300 possible grave sites, all of which were originally identified through the study of aerial imagery. Out of these, 80 produced evidence proving they were actual burial grounds, dating back 3,000 years or more.
Making projections based on the results of this work, the experts conclude that there must be somewhere between 900 and 1,000 actual burial mounds or tombs scattered about the central interior region of the Netherlands.
“It was a small sample, which showed that any site identified as a burial mound by eight to 10 citizen scientists was 80 to 90 percent sure it was indeed a burial mound,” Kaptijn said, summarizing the methodology of the volunteer-based study.
“There are more than a thousand that have a very high chance that they are a burial mound. We could never have imagined that in advance. If we were to investigate them all, we would still be busy for a few years.”
Whether similar concentrations of mounds might be found elsewhere in the country is currently unknown. But the resounding success of this project seems certain to spur more searches.
Singing the Praises of the Citizen Scientist
Performing onsite excavations, the members of the Heritage Wanted team were sometimes able to identify actual mounds through the presence of cremation jars. In other instances, the corpses that had been buried there in the first or second millennium BC left behind telltale traces.
“The bones have already decayed in the Veluwe soil, but we do see a corpse shadow: a discoloration of the soil,” team leader Kaptijn said.
During the next phase of the Heritage Wanted project, Dutch archaeologists, both amateur and professional, will be able to deepen their comprehension of the region’s distant past through their continuing study of these Bronze and Iron Age burial mounds .
“Above all, this gives us more knowledge,” Kaptijn stated. “That has a huge impact on archaeology, from the knowledge of society in the past. And we can better protect the hills for the future, now that we know where they are and have mapped them. It gives us more knowledge of prehistory.”
Perhaps the most extraordinary element of this discovery is the involvement of so many Dutch citizens, who acted as valuable helpers or facilitators for the trained experts, who would have been overwhelmed by the size of the project without such assistance. Because of the unique and innovative nature of this initiative, the Heritage Wanted project was the recipient of the European Heritage Award/Europa Nostra Award for 2022, a prize given out annually by the European Commission. This award celebrates the efforts of cultural heritage organizations that have made major contributions to the preservation and understanding of ancient cultures in Europe.
“One of our main aims was to be able to draw up an inventory of what there is, so we can protect it,” Eva Kaptijn explained. She noted that the project had given participants new insights on how much of the Netherlands’ ancient heritage still remains undiscovered, even in the 21st century.
“They had no idea what there was in their back garden, so to speak,” she said.
Now they do, and so does everyone else in the Netherlands and around the world.
Top image: Citizen scientists investigating a potential burial mound location. Source: © Heritage Gelderland
By Nathan Falde