"These are magnificent creatures, a true American icon, and they should be treasured and preserved," said Pickens, who is working to create a million-acre sanctuary capable of taking all 30,000 horses currently held in captivity by the Bureau of Land Management.
Pickens, in a moving address to the House of Representatives Subcommittee on National Parks, Forests and Public Lands, said: "Probably no other image around the world symbolises America like that of the wild horse.
"Over the past year I have been inundated with media inquiries about my proposal from the United States and all around the world - including documentaries, newspapers, radio, and television from Germany, France, Sweden, Australia, the Czech Republic, England, and Japan.
"They are captivated by and curious about the thought and imagery of America's natural history.
"They don't have such a wild and romantic past. While England may have the tales of Henry the VIII and his wives, and France may have had Napoleon and Josephine, we in America were blessed to have had Lewis and Clark, cowboys and Indians, the Pony Express and wild horses," Pickens said.
"These great individuals and the stories of the West are not mythical; they are real. They are the fabric that made up America. We need to respect our history and respect our God-given heritage.
"While other countries have their history in books and museums, our history is a living museum. Let's allow the American people to have the chance to enjoy and experience these reminders of our history which are alive and well today roaming the West.
"Let children from big cities have the opportunity to view the treasures right here in the United States, encourage our Boy Scouts and Girl Scouts to come and experience nature and its inhabitants. Let everyone see and appreciate the foundation upon which our great nation was established, by ensuring wild horses are protected and enjoyed forever. Let's share this with the world."
Pickens, the wife of Texas oil tycoon T. Boone Pickens was addressing the subcommittee on the Restoring Our American Mustangs (ROAM) Act, which would ban the slaughter of healthy wild horses.
She said she had been in talks with the Bureau of Land Management (BLM), which is responsible for the management of wild horses and burros, for some time over her plans for a private wild horse sanctuary.
"The wild horse sanctuary would receive and care for some 30,000 wild horses currently in short- and long-term holding facilities, thereby saving the BLM, and the American taxpayer, approximately $US700 million by 2020.
"It is time to think big about how we can improve the Wild Horse and Burro Programme, both operationally and legislatively.
"I first became interested in the plight of wild horses and burros when working with others to end the slaughter of American horses ... The more I learned of their management by BLM, however, the more despondent and frustrated I became.
"It makes no sense, either from a fiscal or humane perspective, to manage a programme to the point where more horses are in holding than are on the range, and where the proportion of animals in captivity to those in the wild will only increase as the years go on.
"It doesn't make sense for the horses, and it doesn't make sense for everyday Americans who are footing the bill."
Pickens told the subcommittee she had been actively seeking appropriate land with sufficient forage, water sources, and more. "The animals will be free-roaming and able to form natural bands. While the primary objective of the project is to care for these wonderful creatures, we will also be stewards of the land.
"In short, the opportunity we are presenting to the BLM should be used to improve their image and the public's perception of the wild horse and burro programme," she said.
"The sanctuary I am seeking to create will be good for America's wild horses and burros, good for American taxpayers and good for the BLM.
"If this can be rolled out in tandem with some of the legislative fixes included in the (ROAM) act, we will have an opportunity to effect real change."
Pickens said she backed the wording in the Act that would overturn the Burns Rider, thereby restoring protections included in the original 1971 Act that were designed to prevent the slaughter of America's wild horses and burros.
"It is crucial that these protections be reinstated so as to ensure that our mustangs never have to endure the horrors of slaughter. No horse, wild or otherwise, should be brutally butchered for human consumption."
Pickens said she was not born in the United States, but from the time she was a little girl she "had dreamed of coming to this incredible country".
"I was filled with visions of the Wild West, where horses roamed free and individuals such as John Wayne exemplified an image of strong yet compassionate people."
Americans, she said, needed to respect that great heritage.