ON a clear, sunny day, Beacon Hill, above Pickering, offers sweeping views over the North Yorkshire market town and across to the green fields of Ryedale beyond.

But anyone who takes a stroll to the crest to enjoy the view may not realise that beneath their feet is the legacy of an age when nuclear war was as much a threat as Al Qaeda is today.

Until 1968, there were 1,563 nuclear bunkers across the UK which would have monitored conditions on the surface in the wake of an apocalypse.

Manned by the Royal Observer Corps, each would have kept track of any further explosions and the likely direction in which any fallout would be drifting.

But few of the secret bases matched the stereotypical movie image. There were no swishing doors activated by swipe cards, no plasma screens projecting images of an unfolding crisis, and no monorail to carry officials deep beneath the earth.

Instead, most of the three-man teams would squeeze into a single room wide enough to accommodate a bunkbed, a couple of canvas chairs and a stove, with a chemical toilet in the only other room.

All the concrete bunkers were permanently manned in the 1950s and early 1960s, when the Cold War was at its coldest, although half were decommissioned in 1968.

But, perhaps surprisingly, the remainder, including the post beneath Beacon Hill, remained fully operational until 1992, when the collapse of communism behind the Iron Curtain signalled a new era in world politics.

A handful of the old bunkers have since found their way on to the open market, some selling as curiosities and others to buyers convinced the free world is still under threat - including one man who feared attack from outer space.

But, from today, Pickering's bunker is among a clutch of 11 to be offered for sale by auction on the Ebay site on the Internet.

Rob Ward, a spokesman for agents J H Walter, said: "We handled the sale of three other bunkers in Lincolnshire and Nottinghamshire earlier this year and were staggered by the response.

"One made over £8,000 and the others even more so. Given the stunning location of some of the new sites, we are anticipating plenty of interest."

Although some of the artefacts of a bygone age are still intact at the Pickering bunker, including a 1991 calendar, soap, first aid box and recording documents, vandals have managed to penetrate what was designed to defy the might of the USSR.

Mr Ward said: "Nevertheless, people have still been showing genuine interest. At first, some have obviously had an image of an underground building big enough to take 50 council workers in their heads but, even when they learn the truth, they have remained intrigued."

Anyone who would like their very own bolthole in the event of a nuclear armageddon can bid until June 1 in an auction at www.ebay.co.uk.

Prospective buyers are also welcome to visit the site on Sunday, between 11am and 4pm. For more details, call J H Walter on (01522) 526526.