If a 17,500-square-foot penthouse triplex in New York fetches its asking price of $250 million, it will be the most expensive home in the United States—exceeding the $238 million that hedge fund billionaire Ken Griffen paid for a condo across the street on “Billionaire’s Row.”

It will also outpace Michael Eisner’s asking price of $225 million for his Malibu, California, estate.

So reports the Wall Street Journal, noting the burgeoning market for $100 million-plus homes in New York, Malibu, Miami and Palm Beach.

“The nine-figure club is a special club, and that club is also now looking to own nine-figure real estate,” listing broker Ryan Serhant of Serhant realty tells WSJ. “It’s a new paradigm now. The uber-wealthy are looking for places to diversify assets, and real estate has become one of the most popular and sought-after mega assets.”

Spanning the 129^th to 131^st floors of Central Park Tower on 57^th Street, the condominium—which goes on the market Monday—boasts 30-feet-high ceilings, a staircase winding through the three floors, a ballroom and seven bedrooms. Its most phenomenal attribute is 1,400-square-foot terrace with 360-degree, unobstructed views.

Developer Extell Development waited until construction of the tower, which began in 2014, was completed this year before putting the penthouse on the market.

Gary Barnett of Extell admits the $250 million price tag is high but says it amounts to $15,000 per square foot and that a nearby apartment on Park Avenue is priced at $20,000 a square foot, without a terrace.

Barnett describes the penthouse as “unique in the world.” Extell is marketing the place as a “mansion in the sky.”