AS the prospect seems to have subsided somewhat, it's probably safe to reveal now the British Government didn't anticipate many fat people surviving a nuclear attack during the Cold War.

At least that's the assumption to be drawn from a cursory inspection of a nuclear bunker built circa 1961 on a hilltop overlooking Upton-upon-Severn.

The reason is quite simple. Anyone carrying a few spare stones wouldn't have got in it. The entrance is down a narrow vertical shaft that drops 30ft and is navigated by a thin iron ladder clamped to the wall.

It's very dark, there's not much room either sideways or backwards and even our agile photographer Jonathan Fuller-Rowell, the racing snake of the editorial department, had to go carefully.

Certain others would need a jemmy and a stick of dynamite to free them once they got stuck. Which would be a real prospect if you had to descend rapidly.

Fortunately, this never happened, and in all honesty was never likely to have done. Because these small bunkers, which were dotted every 15 miles across the countryside, were not really designed as places of safety for the hoi polloi, but as bomb proof control centres for specialist crews who raised the alarm in the event of a nuclear attack.

If you lived close enough to a shelter and knew where it was, you might have had a go at getting in. Although it could likely only accommodate the first 10 to arrive. Failing that, the official advice was to go home, stay indoors and "make yourself safe".

Seeing as nuclear bombs usually flattened everything within a five-mile radius, this was of limited value.

When the Cold War thawed and Maggie Thatcher, Ronnie Reagan and Mikhail Gorbachev began taking tea together, the threat of a nuclear bomb coming our way from somewhere east of the Urals diminished.

So the British Government decided to sell off its network of shelters. Which is where the saga of the bunker near Upton took a very satisfying turn.

Most of the hideaways across the country had been in the care of the Royal Observer Corps, the RAF equivalent of the TA. But when this part-time organisation was stood down in 1991, the entrance doors were padlocked, the lights turned off and no one visited anymore.

At Upton, the ROC team of 10 had been led by chief observer Berny Male, by day a computer technician at Worcester College of Technology.

When the heavy metal lid to the entrance shaft clanged shut for the last time in '91, Berny thought that was that. Until he picked up a copy of the Worcester Evening News on May 19, 1993, and there on the front page was a story announcing the MoD was selling off its former nuclear shelter at Upton. Suggestions for its future use ranged from storage to a facility for the local Scouts.

"Just for old times sake I decided to put in an offer," he said. "The sale was by sealed bids and so I submitted one for £500.

"I was absolutely amazed when I got it. Do you know some have appeared on e-bay recently for £20-£30,000?"

Berny, though, is not about to cash in on his acquisition.

After all, there on the entrance door is the official list of ROC personnel who looked after the shelter with his name at the top - CO B. Male - so there's a family connection here.

The only outward sign of the shelter is a four-foot-high concrete turret and small adjacent ventilation shaft that stand on high ground in a fenced off corner of a grass field a couple of miles from Upton town centre. Panoramic views stretch across country to the Malvern Hills, Tewkesbury and up the Severn valley.

Lifting the turret's heavy metal lid reveals the vertical entrance shaft and the narrow ladder leading down. Negotiate that and you arrive in an entrance well with two doors. One to a chemical toilet, should the nuclear emergency go on a bit, and the other to the shelter proper, a small room with a work surface on the left and twin bunk beds against the wall at the far end.

Built of reinforced concrete and iron girders, it feels very solid, slightly claustrophobic and not as damp as you might expect.

"There is a hand pump system to pump out any water," said Berny, "but we've never had any in here."

The shelter was designed to be used by three ROC operators at a time, hence its cosy size.

"If news had been received of a possible nuclear attack, the warning would have been sounded by a wind-up siren that gave out a long, continuous note," he added. "Then if there was imminent danger of attack, the operators would have let off three pyrotechnic devices to give three loud bangs.

"When all was safe, the siren would have been sounded again, this time with a warbling note."

Fortunately, as we all know, it never came to that.

Bit by bit, Berny has been re-acquiring the equipment the MoD removed from the shelter when it was sold. Although this is more to restore it as a museum piece and for his own nostalgic interest, than as a frontline nuclear defence.

"It's just a lovely place to come for some peace and quiet or to have a barbecue and chill out," he said.

Nevertheless, it is a reminder of a time when a nuclear bomb could have barbecued us all. Especially the portly ones.