It’s a property with no windows, no running water and no mod cons except for a phone line. But there is parking, the countryside is phenomenal and when Armageddon happens it could be perfect. This week will bring the rare sale of a 1958 nuclear bunker in the Cumbrian Dales near Sedbergh. It was one of about 1,500 Royal Observer Corps monitoring posts built across the UK at the height of cold war fears of nuclear attack. The idea was that three volunteers could live down there for a fortnight, able to measure the fallout after the bombs dropped and broadcast messages to the public. After decommissioning, most of the bunkers were sold off and are today often sites for mobile phone masts. But on Thursday one will be auctioned online for anyone to buy. It is “secure, dry and in its original condition” and has a guide price of £15,000-£20,000. Viewings took place over two hours on Monday afternoon and the Guardian went along to see what you get for your money but also to ask: what sort of person wants to buy a nuclear bunker? “I’m on the edge of a midlife crisis,” joked Barney Strange, a paramedic who had come along with his wife, Harvie. “The idea of owning a nuclear bunker is surely every 14-year-old boy’s dream isn’t it? It is so secluded … truly unique. I know this is a cliche, but there is something about buying a piece of history.” Does the thought of sleeping underground in a small windowless room not fill him with dread? “No, not at all. It fills me with a sense of security. I’m not a caver but I love all things underground.” Jim Demitriou, a national valuer with SDL property auctions, was expecting about 20 in-person viewings, a fraction of the interest the sale has generated. He said the seller had owned the bunker since 2008. “He’s kind of felt he’s had his fun with it, [so] it’s time for somebody else to have fun as well. “He’s gravelled the drive, he’s made sure the phone line is intact, he’s decorated it, he’s cleaned it, it’s dry, it’s got some sofa beds in there … he’s had some fun with it. “You might have your own mobile home or caravan and you pitch up there and sleep underground because it’s a novelty. You can sit outside and admire the beautiful countryside.” The Dentdale valley surroundings, even on a drizzly, misty July morning, are undeniably breathtaking. It is remote but, counterintuitively, has great transport links: it is right next to Dent railway station, the highest mainline station in England. From the road, you would never know the bunker was there. Behind a bush is a small concrete structure with a metal hatch. You descend 12 metres (40ft) down a metal ladder into what is like a small cellar – or cell. Nick and Jo Bradley had travelled from Read in Lancashire. “We like quirkiness and we love it up here,” said Jo. “This is quirky.” Nick said they would go away and have a proper chat about what they would do with it. Warren Bardsley, from Manchester, was interested in the bunker as a retreat as well as its Airbnb potential. “It’s amazing, it’s unique, there is nothing like it,” he said. “But it is also a bit crazy.” Getting down the ladder is not straightforward – at least three people decided against it – but it was easy enough for Dave Moll, from west Cumbria, who is in his 70s and lowered down his walking stick on a rope before getting in. “It is unusual,” he said. “It’s the quirkiness of it more than anything else.” Demitriou said people registering their interest for the auction had all sorts of ideas for the bunker. “Someone has said it would make a great music studio. There are also a lot of people into history who want to buy a piece of postwar Britain for not an exorbitant price. Some people want it as a bolthole where they can be away from everything.” The bunker could have a practical purpose if bombs ever do go off – although not for Strange. “I would rather die along with everyone else, I think.”