The Jersey group set up to provide warning of an attack by the Warsaw Pact is disbanding after 47 years.
The bunker was built by the Germans. Picture: Nick Catford
The Jersey Warning and Monitoring Organisation (JWMO) was set up during the Cold War when it was feared Soviet forces might invade Western Europe.
The group's last meeting is on Thursday night at the Trinity Road Bunker where it has met each fortnight.
In recent years the emphasis has moved away from defence and on to monitoring nuclear power stations in France.
The bunker was built by the Germans who occupied the Channel Islands during World War II.
Few modifications have been made since, apart from the installation of a heavy steel and concrete entrance blast door in the 1980s.
The bunker includes a dormitory, canteen and a broadcasting room, formerly run by the BBC.
On a small shelf are the nuclear warning cassettes provided by the Home Office.
There is a filtration plant and generator, but the sirens on the roof were dismantled in 1995.
Members of the JWMO are trained in communications, dealing with casualties and nuclear fall-out procedures.
But concerns about the nuclear threat from the Warsaw Pact have been replaced since the fall of communism in Europe by concerns about radiation from nuclear power stations in France, including at Flamanville, just 30 miles away.
The bunker includes a planning room. Picture: Nick Catford
There are three unmanned monitoring stations in Jersey which measure radiation levels.
Michael Long, Jersey's emergency planning officer, who leads the JWMO, said: "Times do change and it is time to move on to different areas of work.
"It is also time to pay tribute to the members of the organisation for their work over the years.
"They recognise that their time has come."
The bunker will remain in use as for storing emergency planning equipment and Mr Long hopes it will stay open for visitors.
"It has real historic value," he said.
"It has a place in Jersey's heritage which should not be lost."