Deep in the sprawling plains of South Dakota, otherworldly structures like giant molehills are emerging from the ground.
They are sprouting up from a former US Army depot and they don't look like much from the outside, but once you descend beneath the ground things really start to get interesting.
Dubbed the "world's largest bunker survival community", the doomsday bunkers range from luxury underground homes with all the trimmings to minimalist spaces that buyers can furnish themselves.
The Vivos xPoint project now consists of 575 off-grid bunkers capable of housing around 5000 people, and this year they have seen a massive surge in demand.
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The pandemic and the political crises engulfing the US have seen inquiries skyrocket more than 2000 per cent, and some families have already made the move underground.
Described as an "epic humanitarian survival project," CEO Robert Vicino says he first had the idea for the shelters nearly four decades ago.
Vicino said that in 1982 he heard a voice in his head saying he needed to build large, deep, underground bunkers to save thousands of people from an earth-shattering event.
At many points this year it has looked many times like that event was on the cusp of happening, particularly in the US where Covid-19 has spiralled out of control.
Now sales are booming and the company has gone global — boasting a "modern day Noah's ark" in a former Cold War-era munitions storage facility in Germany and a facility in Indiana.
Vicino says most of his customers are middle-class.
He told The Verge many of them were "well-educated, average people with a keen awareness of the current global events and a sense of responsibility knowing they must care for and protect their families during these potential epic and catastrophic times".
And, if you were thinking life in an underground bunker sounds pretty grim, you might be surprised with the level of effort that's gone into making life as palatable as possible for the doomsday preppers.
According to Vicino, the bunkers can sustain life for at least a year, with deep underground wells providing freshwater, filters purifying the air, and even the capacity to grow fresh food.
He said there are gyms, small surgical clinics and even a jail where the psychologically disturbed can be detained.
If this all sounds like your kind of place, you can pick a unit up from $80,500 (US$57,000).
If you're really looking to push the boat out for the end of the world you can get your hands on a "four-star fit-out" which costs $250,000 (US$179,000).
The bunkers are situated on private roads, each with enough floor space to accommodate 10 to 24 people and capable of withstanding a 500,000lb blast — which is reassuring.
Vicino said he believed sales were increasing because of fears the pandemic would end in total chaos.
Speaking to Sky News, one bunker buyer said his "immunocompromised" wife was "terrified" by the rise in coronavirus.
Tom Soulsby said this led them to make the decision to get away from the "millions of people that could infect us in days".
"More than anything, the main protection you need is from people," he said.
"I don't think it's any more paranoid than keeping a fire extinguisher in your house."
Soulsby said he does not trust the government to protect him in the event of a major disaster.
It's not just Vivos that's seeing a spike in interest as luxury doomsday options increase across the US.
In 2017, LinkedIn co-founder Reid Hoffman told The New Yorker that he estimated over 50 per cent of Silicon Valley billionaires already had purchased some kind of apocalypse insurance, like a safe room, bunker, or overseas escape. And, the luxury offerings are growing.
A 51-year-old Florida entrepreneur who owns multiple "fortified locations" around the US says his bunkers' 2.7m-thick epoxy-hardened concrete walls can withstand direct nuclear strikes.
One of them — buried four storeys below central Kansas — is dubbed the most lavish and sophisticated private bunker in the world.
The Guardian reports Hall bought the US$15m silo in 2008 for US$300,000 and that by 2010, he had transformed the 60 metre-deep building into a 15-storey luxury bolthole, where up to 75 people could weather five years inside the sealed, self-sufficient bunker.
A reporter who went down there said there was even a supermarket complete with shopping baskets, cold cabinets and an espresso machine behind the counter.
"The original blueprint for the renovation, it just said 'storerooms' on this level. The psychologist we hired for the project took one look at that and said, 'No, no, no, this needs to feel like a miniature Whole Foods supermarket," Hall told the newspaper.
"We need a tile floor and nicely presented cases, because if people are locked in this silo and they have to come down here and rifle through cardboard boxes to get their food, you'll have depressed people everywhere.'"