The largest home ever built in Beverly Hills, Greystone manor, wasn't built by a movie star, even though many movies have been filmed at this spectacular estate.

Beverly Hills is known for its many grand mansions. Unfortunately, you can only drive past most of these majestic estates. But here is a surprising exception to that rule. At Greystone Park, can drive through the fancy wrought-iron gates of one of the most dramatic estates in Beverly Hills, stroll its lushly landscaped, 16-acre grounds, and admire the 55-room castle up close. And it's all free!

This fortress-like Tudor mansion was built by famed oil-tycoon Edward Doheny in 1928, as a gift to his son. With over 46,000 square feet of living space, it cost more than $4 million to build back then (one might imagine what it would cost today). Many people hail this massive home as one of the grandest mansions on the West coast, second only to William Randolph Hearst's San Simeon (although, to the casual visitor, the mansion may not seem to merit that kind of praise).

Several Hollywood movies have been shot here at Greystone, using the stately mansion and its gardens as backdrop.

It was a Starfleet hospital in "Star Trek: Into Darkness", and also appeared in "X-Men",  "The Social Network", "The Muppets" and "National Treasure: Book of secrets".

In 1993's "Indecent Proposal," real estate agent Demi Moore showed millionaire Robert Redford through the empty living room of the mansion. (He didn't like it.)

Remember the scene in the 1998 "Godfather" spoof, "Mafia!," where Christina Applegate walks into the family dining room and announces "Oh good, Italian food!"? That scene also was shot in the Greystone mansion.

In the Spider-Man movie series, Greystone was the home of Harry Osborne's father: AKA The Green Goblin.  In the X-Men films, Greystone's was courtyard was used as the exterior of the Xavier Institute for Higher Learning.

In the movie "Town and Country" (with Warren Beatty, Dianne Keaton & Goldie Hawn), the home stands in for Charlton Heston's mansion in Sun Valley.

Other films shot here include "What Women Want" (with Mel Gibson), "The Bodyguard" (starring Kevin Costner and Whitney Houston), "The Phantom" (with Billy Zane), "The Witches of Eastwick" (Jack Nicholson & Cher), "The Big Lebowski" (with Jeff Bridges), "All of Me" (Steve Martin & Lily Tomlin), "Ghostbusters II" (Dan Aykroyd & Bill Murray), "Death Becomes Her" (Goldie Hawn & Meryl Streep), "Jumpin' Jack Flash" (starring Whoopi Goldberg), "The Beautician And The Beast" (with Fran Dresher), "Guilty By Suspicion" (Robert De Niro), "Air Force One" (with Harrison Ford), "Nixon," "Batman & Robin," "Heat,"  "The Loved One," "Forever Amber," "The Winds of War," and "Dynasty, the Movie." They shot an episode of "Alias" here. And back in 1991, they shot episodes of the vampire soap opera "Dark Shadows" here.

On TV's "Gilmore Girls," Greystone was seen as the exterior of Chilton Preparatory Academy, the prestigious private school that Rory (Alexis Bledel) attended.

1994's "Richie Rich" installed special iron gates with "R.R." initials. And it was the Greystone manor bowling alley that was seen in the predictably bloody end to 2007's "There Will Be Blood".

Even the famous marriage of "Luke & Laura" on TV's "General Hospital" was shot in the gardens of Greystone (where it posed as the Port Charles Mayor's mansion.)

Actor James Woods was married - for real - at the estate.

So was Kirk Douglas. In May of 2004, Mr. Douglas and his wife of 50 years, Anne, were re-married at Greystone, at a ceremony with 300 guests in attendance, including Lauren Bacall, Nancy Reagan, Tony Curtis, Karl Malden, Merv Griffin, Sidney Sheldon, Red Buttons, Don Rickles, Angie Dickinson, Jennifer Jones and many more.

In 2001, the Elton John music video "I Want Love," was shot in one seamless take; it shows actor Robert Downey Jr. wandering about inside the Greystone mansion, lip-syncing the words to the song.

In September of 2008, then Presidential candidate Barack Obama held a $28,500-per-plate fundraiser at the Beverly Hills mansion, which drew the likes of Leonardo DiCaprio, Steven Spielberg, Tobey Maguire, Jodie Foster, Eddie Murphy, Barbara Mandel, Antonio Banderas, Will Ferrell and Jamie Lee Curtis.

The estate has been leased on a semi-permanent basis by the American Film Institute. So don't be surprised if you bump into a film crew shooting yet another movie.

Alas, the home is now empty, and is closed to visitors; there are no regular public tours of the house itself. Most months we are limited to exploring the peaceful, forest-like grounds surrounding the home, with an occasional peep through a dusty window for a brief glimpse of the mansion's vast interior.

However, they DO sometimes offer a short series of classical (chamber music) concerts each year, held inside the living room of the mansion, and other special events when the mansion interior can be seen (usually for a fee).  You can check their special events calendar here.

Despite their incredible wealth (a fortune of over $100 million), the members of the Doheny family had their share of tragedy. Edward Doheny was involved with bribery charges in the infamous Teapot Dome scandal, and his son's life ended in a bizarre murder-suicide at the home. The son's widow lived on at Greystone until 1955. The estate was eventually willed to the city of Beverly Hills, and it is now a public park.

But few people seem to know about it; Greystone is one of L.A.'s better kept secrets.

The park's hilltop parking lot offers a magnificent panoramic view of the city below. You'll also find a bulletin-board nearby, studded with black and white photos which show the Greystone estate during its glory days.

A self-guided tour of the grounds will take you along a maze of winding stone walkways and brick stairways, past sweeping green lawns and wonderful vistas, sculpted hedges, hidden courtyards, and lush landscaping. Keep to your right as you make your way downhill, and you'll eventually find the paths that lead to the mansion itself. (There's a lot of walking and stair-climbing to be done here, if you wish to fully explore the estate, so wear comfortable shoes and be ready for some exercise.)

( It can be a little tricky to find your way from the parking lot, through the gardens, to the house itself. It might pay to study the maps found here, in advance of your visit. )

The mansion resembles a modern castle, with three-foot-thick grey limestone walls, heavy wooden doors, stone courtyards, and a slate roof; it's not hard to figure out why they called it "Greystone"...

There is a tranquil, rarefied atmosphere up here on the hilltop, amid the towering redwoods. There's a pine scent in the air, and every turn seems to reveal a new view of the cityscape below.

Take a peek through the smudged windows of the mansion. A brief look reveals vast marble halls and glorious old ballrooms, replete with parquet floors, crystal chandeliers, massive marble fireplaces, and sweeping stone archways. This is where Robert Redford and Demi Moore walked during their scene in "Indecent Proposal."

Even so, all is not well in paradise.

The house and grounds, for all their former grandeur and current beauty, seem uncommonly vacant and aloof today. Like a giant stone castle abandoned in some tragic fairy tale, the home sits vacant and forlorn, its rooms now empty of both furniture and of the people who once brought the house to life. There is an undeniable sadness to this deserted mansion.

Likewise, the beautiful grounds have been fairly well maintained, but not with the same kind of loving care that a devoted owner would lavish on such a handsome estate. Mr. Doheny must have loved water, because the property is dotted with numerous swimming pools, fountains, reflecting pools, waterfalls and ponds. Yet, almost all of these now stand bone dry and melancholy. Only one tiny lily pond remains filled, but the large koi fish that swim in it seem oddly listless as they drift among the lily pads.

Greystone Park is well worth a visit. After all, how often do you get invited to a millionaire's grand estate in Beverly Hills? But the mansion has such wonderful potential that it seems a crime to let it sit empty and idle. With a little effort, the home could be opened to the public for docent-led tours; the history of the property told to visitors. At least a few of the mansion's 55 rooms could be furnished and restored to their former grandeur, and perhaps rented out for festive occasions...

As it is now, the mansion seems chilly and lifeless.

There were too few visitors to the park when I last visited, on a warm Sunday afternoon; just an occasional family on a picnic, or an out-of-town tourist, which only added to the estate's sense of isolation. Fortunately, there is a park ranger on duty, stationed near the mansion's rear courtyard. And even in its current diminished condition, Greystone is still a sight to be seen.

On April 15, 2000, President Bill Clinton visited the Greystone mansion, the site of a major fundraiser hosted by DreamWorks partners Steven Spielberg, Jeffrey Katzenberg and David Geffen. This wasbe the President's second visit to Greystone; a 1999 fundraiser was also held there, and featured opera singer Andrea Bocelli. Among stars on the guest list for the dinner at Greystone Mansion in Beverly Hills were Meg Ryan, Dennis Quaid, Goldie Hawn, Kurt Russell and Whoopi Goldberg.

The park grounds are open daily: 10 a.m.- 5 p.m.(until 6 p.m.in the summer months); the mansion itself is not open to the public. Parking is in a free hilltop parking lot, within the gates. No admission charge.

Getting there: From Hollywood & Vine, go west on Sunset Blvd. (about four miles, to a few blocks past the city limits of Beverly Hills) to where there is a fork in the road with Doheny Road (not to be confused with the major north/south Doheny Drive a few blocks to the east). Here, where Sunset veers off to the southwest, continue straight west on little Doheny Road, for about five short blocks to Loma Vista Drive. Turn right (north) on Loma Vista Drive, and go a short distance to the park entrance on the left (west) side of the street. Turn left into the park's main gate and drive up a steep, winding road to the hilltop parking lot.