NY- Forget a simple “For Sale” sign – the $59 million upper East Side mansion once owned by fallen porn king Robert Guccione was advertised with a full-color, four-page insert in The New York Times yesterday.

The Penthouse magazine founder lost the home a year ago to creditors picking over the remains of his business empire. But after a year on the market, the sprawling townhouse remains unsold.

So the broker, the Corcoran Group, is reaching out to potential buyers – “from royalty to hedge funds,” said the company’s Lisa Simonsen – with a brochure that looks as high-toned and classy as Penthouse wasn’t.

“Instead of diamonds this year …” reads the cover line under a photo of the mansion’s 9-foot-deep swimming pool, which sits in a room decorated with European friezes and statues.

Other photos show the Carrara marble staircase, terraced gardens and an ornately carved fireplace mantel from the 20,000-square-foot home, reputed to be Manhattan’s largest private residence.

The property, on E. 67th St. near Madison Ave., traces its history to a six-story mansion built in 1879. That was combined with a neighboring building in the 1920s to make a rare double-wide townhouse with 25 rooms. Guccione renovated it extensively, if gaudily – think gold-plated bathroom fixtures.

The original asking price was $99,999,999, but Corcoran has knocked it down to $59 million. That’s still higher than the $53 million record set last fall for an E. 75th St. townhouse – but Corcoran says the price is negotiable.

“We’re open to dialogue,” Simonsen said.

Property taxes run an eye-popping $283,672 a year, and the upkeep is astronomical.

“Maybe if you’re worried about the maintenance, this property is not for you,” Simonsen said.

The insert ran only in New York editions of the newspaper, Simonsen said. Guccione now lives in an undisclosed location in California.

“This is kind of in his rearview mirror,” said Guccione’s attorney, Robert Feinstein. “He’s living out in California. He’s in good health.”