In the new study, Sturdy Colls and her team found physical evidence supporting witness accounts of harsh conditions at Sylt. They mapped the surviving shallow depressions of the barracks at the camp, confirming witness reports of overcrowding; each prisoner would have had just 16 square feet of space at best. Through the course of removing vegetation from the site, they uncovered the prisoners' toilets. The team made virtual-reality visualisations for a clearer view of features—such as an underground tunnel leading from the commandant’s house to the camp—that were difficult to see in the field due to bad lighting conditions.

Using historic aerial images, the researchers also tracked how both the size and security measures of Lager Sylt drastically increased when it evolved from a labour camp to a concentration camp in 1943.

The SS, for instance, went to great lengths to outfit Lager Sylt with imposing fences and guard towers, which surely had a profound psychological effect on the inmates.

“In a way, it didn't need any of those things because it was on a corner of a small island surrounded by minefields,” Sturdy Colls says. “There was nowhere for any of these prisoners to go.”

Remembering Sylt

How the legacy of Lager Sylt and Alderney under Nazi occupation should be presented is still a matter of debate. One of the few clearly visible elements that remain of the camp is the main gate. Today it is marked with just a small plaque, placed there in a ceremony in 2008 at the request of former prisoners.

Proposals to excavate at Lager Sylt have thus far been denied, Sturdy Colls says, which has made her team's no-dig, forensic study of the Sylt site all the more important.

“We’re not the first people to discover this camp existed—but despite all those testimonies and despite all those previous efforts, the history of the site was still not known, ” Sturdy Colls says.

The work we did was trying to help the stories of the people who suffered be known more widely.”

"In my opinion, the paper will be useful in helping the island of Alderney to see the extent of traces of Lager Sylt left in the landscape and therefore to think again about how the camp might be used in the island's heritage strategy in the future," says Gillian Carr, an archaeologist at the University of Cambridge. Carr has studied the occupation of the Channel Islands but was not involved in this recent study.

In late 2017, the Alderney government did formally designate Lager Sylt a conservation area, barring development that would threaten the site. Graham McKinley, an elected Member (legislator) of the States of Alderney, says he would like to see the Lager Sylt site made more accessible to visitors. He's trying to re-establish a heritage committee that would explore how the location could be studied, preserved and made into a memorial site.

"There is still a small group of people who want to put the past behind them and continue without looking into it too much," says McKinley. "I believe we should be doing a lot more to show the world what actually happened here."