Bronwen Brown went to look inside the previously sealed wartime bunker.
A previously sealed German bunker dating back to the Second World War is being excavated for the first time in decades.
Guernsey's fortification at L'Ancresse was one of hundreds of concrete structures built by slave labourers during the Channel Islands' occupation by Nazi forces.
Work excavating the site has been carried out by local historians at Festung Guernsey.
When the group first unsealed the bunker, they discovered a long tunnel underground leading to the remains of a fixed gun emplacement, gas pipes, phone cables and German military signage stencilled onto the walls.
Paul Bourgaize has coordinated the project. He said there is still more to uncover before it is restored and re-opened to the public as a museum.
"There’s an awful lot of soil, backfilled rubble that’s got to come out so that will take months," he told ITV.
"From there we will sort of start gradually conserving it and adding original artefacts."
The Channel Islands were the only part of the British Isles to be captured by Nazi forces during the Second World War.
Each new discovery allows local historians to find out more about life in Guernsey during the Occupation.
Annette Henry, who gives guided tours of the island's fortifications, said: "I’ve worked with thousands of visitors who have been none the wiser that the Channel Islands were the only part of British soil that was occupied during the Second World War.
"When they see the number of structures here, the bunkers, the batteries, the towers, the underground tunnels we have over 900 structures in Guernsey alone and so they just don’t realise how much history there is here in Guernsey."
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