The oil tycoon bought the property in 1971.
America's most expensive property on the market has opened its doors to Inside Edition for a special tour.
The Texas ranch has been owned by oil tycoon T. Boone Pickens since 1971, and is currently on sale for $250 million.
Much of the sale will benefit Pickens' charitable foundation. He has given more than a billion dollars to various causes over the years, and has told his five children that he doesn't believe in big inheritances.
There is oil on the 65,000-acre ranch, as well as a kennel for 50 dogs.
The 33,000-square-foot main house has vaulted ceilings, a magnificent gallery featuring western artwork and leads into a plush, two-story library and a movie theater.
“We had sports figures, political leaders — [a] lot of deals been done here,” Pickens' chief of staff, Jay Rosser, told Inside Edition. “He's certainly sad to see it go.”
There is an industrial kitchen and six guest suites, including one where Nancy Reagan once stayed.
The property spans over 100 miles and is known as the Mesa Vista Ranch, which combines homes and lodges, as well as a chapel to host weddings.
Pickens even had a private residence on the estate, which is perched on a hill and offers breathtaking views of the landscape.