Mark Zuckerberg plans to build $270m underground bunker in Hawaii: report

Meta CEO Mark Zuckerberg and his wife Priscilla Chan plan to construct a 5,000-square-foot underground shelter on their Hawaii ranch, supplying it with energy and food, TIME reported citing a Wired investigation.

The investigation, published earlier this month, revealed that the tech billionaire's shelter on Kauai's Ko'olau Ranch will feature metal doors filled with concrete, similar to bunkers and bomb shelters.

The 1,400-acre compound, which includes over a dozen buildings with at least 30 bedrooms and 30 bathrooms, based on planning documents acquired by Wired, includes two stand-alone mansions, 11 treehouses, a fitness centre, guest houses, and operations buildings.

The partially completed compound is part of the sprawling 1,400-acre Ko'olau Ranch compound.

While the purpose of an underground shelter in Kauai County remains unclear, a spokesperson for Zuckerberg and Chan stated that the county encourages homeowners to build shelters and offered residents a tax break for building hurricane-resistant safe rooms two decades ago.

"Mark and Priscilla value the time their family spends at Ko'olau Ranch and in the local community, and are committed to preserving the ranch's natural beauty," Brandi Hoffine Barr, told TIME via email.

The couple bought the property, which was planned to house 80 luxury homes, but now they're developing on less than 1% of the land, focusing on farming, ranching, conservation, open spaces, and wildlife preservation.

Silicon Valley's elite have been buying up property and trying to build bunkers for years, The Guardian has reported.

Entrepreneurs are selling luxury underground apartments for disaster preparedness, and super-rich doomsday preppers have asked Douglas Rushkoff, author of 'Survival of the Richest', about guarding their food supply in the event of a disaster.

Whatever the purpose, the cost to build the new Zuckerberg-Chan compound is expensive — along with the land, it is pegged at upwards of $270 million, Wired reported.

Construction and other workers on the property were reportedly made to sign strict non-disclosure agreements (NDAs), according to the news outlet, a question about which was not addressed by Hoffine Barr in her emailed response to TIME.