(NewsNation) — Meta founder Mark Zuckerberg is building a massive Hawaiian compound complete with tree houses, dozens of bedrooms and even an underground bunker, according to an investigation by Wired.

The in-depth investigation by Wired said the compound is being built in Kauai, Hawaii, and reportedly cost $100 million to build.

The Wired investigation cited sources and planning documents obtained through public records requests.

Koolau Ranch, as it is reportedly called, sits on land purchased by Zuckerberg for $170 million.

What’s in the compound?

The ranch will have at least 30 bedrooms and 30 bathrooms and a network of tree houses that connect some of the rooms, according to Wired.

Wired reports that the main residences will be joined by a 5,000-square-foot underground shelter that includes living spaces and an escape hatch. Sources told Wired the compound will be completely self-sufficient, with an 18-foot tall water tank and pump system and food production systems.

How are Hawaii locals reacting?

Hundreds of workers and trucks have come and gone from the property during construction, while some workers have reportedly been fired for talking openly about the project.

Some of the locals are not happy, though Zuckerberg’s representative said he is committed to preserving the natural beauty and only one percent of the land will be developed.

There have been complaints about noise and traffic during construction, as well as a larger debate about billionaires buying up land in Hawaii while residents struggle.

Zuckerberg’s net worth was estimated in December at $119 billion by Forbes, making him the sixth richest person in the world.

What are doomsday preppers?

Doomsday preppers are stocking up for the end of the world or at the very least, major calamity. Preppers may learn survivalist skills as well as stockpiling supplies such as food and ammunition.

Some preppers go as far as constructing bunkers that could survive a catastrophic event like a nuclear bomb. One of the world’s largest bunker communities is at an old Army base in South Dakota.

Renamed Vivos, NewsNation visited the community where former military, doctors, lawyers, school teachers and others are buying up bunkers from all over the country.

The effort to avoid the end-of-the-world event isn’t cheap. The bunkers in South Dakota run around $55,000 unfinished, which is still a lot less than Zuckerberg is spending in Hawaii.

Is Mark Zuckerberg the only celebrity making plans for doomsday?

The Facebook founder is far from alone in his plans. A number of Silicon Valley billionaires have been rumored to be buying up land in case of an apocalypse.

Some well-known celebrities are preparing for the worst as well, including Transformers star Josh Duhamel, who has admitted to becoming a prepper. Reality star Kim Kardashian has also been reported to be a prepper.

Other celebrities who are known or rumored to be preppers include sitcom star Roseanne Barr, who has advocated for organization with neighbors, actor Jamie Lee Curtis, who has worked with the Red Cross to promote emergency preparedness, actor Nathan Fillion, who learned welding to prepare for the zombie apocalypse and former UFC star Ronda Rousey, who has a homestead and is raising chickens.

Click here to read the full investigation from Wired.