Lifestyle Home Inside America's Most Expensive Home: A 100,000 Sq. Ft. Mansion Asking a Rumored $350 Million The over-the-top Los Angeles estate known as "The One" has been in development for almost a decade By Mackenzie Schmidt Mackenzie Schmidt Mackenzie Schmidt is the Home and Travel Editor for PEOPLE. She's worked at PEOPLE for over five years as a writer and editor on the Lifestyle team. People Editorial Guidelines Updated on May 25, 2022 10:49 PM Share Tweet Pin Email Photo: Douglas Friedman/ Architectural Digest A one-of-a-kind home in Bel Air, California, is claiming the title of the world's largest and America's most expensive residence. The mega-mansion, dubbed "The One," offers a mind-boggling 105,000 square feet of living space and will hit the market for a rumored $350 million. The headline-grabbing property has had several superlative claims made about it over the years it has been under construction, including that it would be listed for as much as $500 million in 2018. In a 2017 feature, the New York Times pointed out that the house would likely sell for much less than that attention-grabbing asking price, citing that the Playboy mansion sold in 2016 for $100 million, after being listed for $200 million. At the time, the most expensive house ever sold in the U.S. was a $137 million property in the Hamptons. The world record was a $300 million French chateau, purchased by a Saudi prince in 2015. While its list of wild amenities (see below) has been touted throughout its nearly decade-long development, the now-completed interiors of the 21-bedroom, 42-bathroom home are being revealed for the first time in an Architectural Digest feature. This Insane $500 Million Mansion is About to Be America's Most Expensive Home for Sale Douglas Friedman/ Architectural Digest Aside from the sheer size, some of the most jaw-dropping features include the moat that surrounds the property on three sides, a 400-foot-long jogging track, a 30-car garage with two "car-display turntables," bowling alley, spa, cigar lounge, five swimming pools and 30-seat movie theater. There's also a "philanthropy wing," which can host 200 guests for charity galas and has something called "sky pods" that overlook the city. The home wasn't built for a particular client, but rather as a project for owner and developer Nile Niami, who hired architect Paul McClean and designer Kathryn Rotondi to bring his vision to life. McClean also designed Jay-Z and Beyoncé's new L.A. pad, which they purchased for $88 million in 2017. Douglas Friedman/ Architectural Digest "This project has been such a long and educational journey for us all," McClean tells archdigest.com. "It was approached with excitement and was thrilling to create, but I don't think any of us realized just how much effort and time it would take to complete the project." According to the outlet, "due to recently approved city ordinances, a house of this magnitude will never again be built in Los Angeles," meaning the lucky listing agents — Branden and Rayni Williams of The Beverly Hills Estates, along with Compass's Aaron Kirman — will truly be selling "The One." See many more photos and read the full feature on archdigest.com.