When Playboy founder Hugh Hefner heard that the campaign to buy the open space west of the Hollywood sign was short about $1 million, he knew he had to step in once again to protect the famous Los Angeles landmark.

“Turned out the kid was back in the water again,” he said in a telephone interview.

So he anted up $900,000, which helped the campaign cross the finish line. On Monday, the Trust for Public Land announced that, thanks to Hefner’s gift and an additional $500,000 from the Tiffany & Co. Foundation and Aileen Getty, it finally had the $12.5 million needed to buy Cahuenga Peak from Fox River Financial Resources Inc.

The 138-acre property, which offers a spectacular 360-degree panorama of the Los Angeles Basin and the San Fernando Valley, now will become part of Griffith Park.

In 1978, Hefner played a major role in a campaign to fix up the then-terribly dilapidated Hollywood sign. Ensuring that the land would remain undeveloped was worth taking action again, he said.

“It’s like saying let’s build a house in the middle of Yellowstone Park. There are some things that are more important. The Hollywood sign represents the dreams of millions. It’s a symbol. It is as the Eiffel Tower is to Paris. It represents the movies.”

The mountaintop once belonged to aircraft titan Howard Hughes, who acquired it in the 1930s hoping to build a love nest for actress Ginger Rogers. (She wouldn’t let him.) It sat unbuilt upon and forgotten for decades until 2002, when a group of Chicago investors bought the land from the Hughes estate at a bargain-basement price.

When they announced plans to subdivide the peak into five luxury home sites and try to sell them off for $40 million, city officials were as shocked as residents.

“Like many people, I had assumed that all the land surrounding the Hollywood sign was part of Griffith Park, " said Liz Kuball, a photographer who lives in Hollywood and donated $10 online.

“I grew up in the Midwest, and although I didn’t move out to Los Angeles to be in the entertainment industry, I did move out here with the complete conviction that things would be better, and they have been. To me, the Hollywood sign represents that promise.”

According to the Trust for Public Land, the campaign — which in February briefly covered the Hollywood sign with the words “Save the Peak” — won support from all over the world, with donors from as far away as Norway and Japan.

The Tiffany & Co. Foundation and Aileen Getty each donated $1 million to kick off the fundraising — and then in the final days offered $500,000 more in a matching grant if the trust could raise the final $1 million. About $5.7 million of the purchase money came from state and local funds earmarked for park land acquisition. An additional $3.2 million was raised from Hollywood A-listers including Steven Spielberg and Tom Hanks. About $200,000 came from online donations from Kuball and thousands of others and from local activists who raised money creatively — with a concert on the Sunset Strip and bake sales.

More than 27,000 people followed the campaign on Facebook.

“This is the optimum makeup of philanthropy. It’s been embraced by such a broad spectrum of interest,” said Sam Hodder, California state director of the Trust for Public Land. “By investing in public spaces like this, we are giving the community a chance to interact together. It’s a great equalizer. This is their mountain now.”

Gov. Arnold Schwarzenegger spoke of the Hollywood sign and the dreams attached to it at Monday’s announcement of the purchase.

“I am proud we were able to come together and create a public-private partnership to protect this historic symbol that will continue to welcome dreamers, artists and Austrian bodybuilders for generations to come,” he said.

L.A. Councilman Tom LaBonge, who was very active in the fundraising campaign, said saving the peak was a once-in-a-lifetime opportunity.

“The Cahuenga Peak is very majestic. This is one mountain you actually could see which is not obscured by houses,” he said. “If we lost this opportunity, we wouldn’t experience what is truly nature in the heart of the city.”

chingching.ni@latimes.com