Billionaires are no strangers to extensive real estate portfolios, and many of them are building their own Doomsday bunkers.

Shall we count Mark Zuckerberg among them? If you ask him, no.

The Meta CEO said on a recent episode of the podcast “This Past Weekend w/ Theo Von” that he does “have an underground tunnel” at his ranch on the Hawaiian island of Kauai, though he resisted characterizing it as a bunker.

“There’s this whole meme about how people are saying I built this, like, bunker underground. It’s like more of underground storage type of situation,” Zuckerberg said. “It’s sort of a tunnel that just goes to another building.”

Zuckerberg’s real estate portfolio includes expansive holdings in Hawaii. He began snapping up land there more than a decade ago. He reportedly paid $100 million for roughly 750 acres in 2014 and $53 million for another 600 acres on Kauai’s North Shore in 2021.

In December 2023, Wired reported that Zuckerberg was building a 5,000-square-foot underground shelter, complete with its own supplies of energy and food, at his Ko’olau Ranch property. The final bill after tallying up building permits and land will be about $270 million, the magazine reported.

Wired reported the Kauai compound would feature two mansions linked by a tunnel that also connects to the shelter, which would have “living space, a mechanical room, and an escape hatch that can be accessed via a ladder,” as well as a sturdy metal door filled with concrete.

Brandi Hoffine Barr, a spokesperson for Zuckerberg and his wife Priscilla Chan, declined to comment to Wired at the time regarding the size or features of the underground structure.

Local news outlet Hawaii News Now reported in December that it had obtained county planning documents showing an underground “storm shelter” measuring nearly 4,500 square feet on his property, roughly the size of an NBA basketball court.

In a December Bloomberg interview, Zuckerberg equated the bunker to “a basement” or “a little shelter.”

“There’s just a bunch of storage space and like, I don’t know, whatever you want to call it, a hurricane shelter or whatever,” he said. “I think it got blown out of proportion as if the whole ranch was some kind of Doomsday bunker, which is just not true.”

Zuckerberg posted a video on Instagram in January 2024 poking fun at the discourse surrounding his property, saying, “When your wife catches you in the ‘bunker’ playing video games.” The clip shows Chan walking into a keypad-operated room resembling a home movie theater where Zuckerberg is seen gaming with friends on a massive screen.

Zuckerberg has also posted on Instagram about starting cattle ranching on the property.

“Started raising cattle at Ko’olau Ranch on Kauai, and my goal is to create some of the highest quality beef in the world,” he wrote in January 2024. “The cattle are wagyu and angus, and they’ll grow up eating macadamia meal and drinking beer that we grow and produce here on the ranch.”

The following month, he said that he was “not trying to do this commercially” and was “just trying to create the highest-quality stuff we can.” He also explained the reasoning behind the cows’ diet of macadamia nuts and beer.

“As a human, what do you think is the thing that basically you just sit and eat a lot? It’s like beer and nuts, basically. Nuts, super dense. Beer induces appetite, which I think people are familiar with.”

He added that he wanted to feed the cows the “densest, most nutritious” food so they would gain weight and “be the most delicious cows.”

In addition to cattle ranching, the land would include “organic ginger and turmeric farms, a nursery dedicated to native plant restoration, and partnering with Kauai’s foremost wildlife conservation experts to protect native birds and other endangered or threatened wildlife populations,” a spokesperson for Zuckerberg and Chan told Business Insider.

“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,” the spokesperson said. “When they acquired the property, they rescinded an existing agreement that would have allowed for portions of the property to be divided into 80 luxury homes. Under their care, less than 1% of the overall land is developed with the vast majority dedicated to farming, ranching, conservation, open spaces, and wildlife preservation.”