Dayton Duncan and Ken Burns

Special for USA TODAY

Last year, as the National Park Service celebrated its 100th birthday, Americans were encouraged to “Find Your Park.”

Park visitors did just that 331 million times, up 8% from the previous year and setting a new record. Those visitors, we’re sure, went home with millions of imperishable memories of connecting with our country’s most magnificent landscapes, its wildlife and its history. They also contributed an estimated $32 billion to the nation’s economy (a $10 return on every dollar Congress appropriated for parks) and supported 295,000 jobs. As birthday parties go, that’s quite a success.

This year, another centennial is underway. Up in Alaska, Denali National Park and Preserve turns 100 years old. If it’s stunning scenery and fascinating wildlife you’re looking for, Denali’s got more of both than any other park you’re likely to visit.

At its heart, rising 20,310 spectacular feet above sea level, is the highest mountain in North America, which the local Athabaskan Indians reverently call Denali, “The High One.” Words aren’t adequate to describe Denali’s dramatic immensity, looming over the Alaska Range. An early visitor likened the experience of seeing it for the first time to looking into the yawning abyss of the Grand Canyon. “At such times,” he said, “man feels his atomic insignificance in this universe.”

One of our own favorite memories in making our PBS documentary, The National Parks: America’s Best Idea, was an August afternoon spent near Wonder Lake in the center of the park. Denali was enshrouded in clouds (as it often is) and we were anxious about whether we would ever capture the mountain’s majesty on film. We made a key decision by recognizing our own atomic insignificance in Denali’s conception of time. We aimed our camera where we believed the mountain was behind the clouds, set it to shoot one frame every four seconds to create a time lapse ... and simply waited.

We swatted mosquitoes. Ate the sandwiches we had packed. Picked a few tundra blueberries for dessert. Decompressed to the rhythms of the breeze and the clouds and occasional sounds of sandhill cranes high overhead, beginning their long migration southward. And waited some more. An hour or two passed.

Then slowly, as if it was pulling back a curtain to reward our patience, Denali revealed itself. We knew we had a “signature” shot for our documentary, and for the next several years in the editing room — and anytime we watch the finished film now, nearly 15 years after the fact — that moment is reborn and reactivates all of our senses.

But as awe-inspiring as the mountain might be, it is the array of wildlife around it that played the pivotal role in making Denali a national park. And, as is so often the case in the larger story of the national park idea, it was the far-sighted perseverance of a single individual that proved decisive in it happening.

Charles Sheldon, a Vermont native, had made a fortune in the railroad and mining businesses, allowing him to retire at age 35 and devote his energies to his personal passion: the study of wild mountain sheep. An avid hunter and skilled but amateur naturalist, his field trips to observe North American sheep had taken him from the mountains of Mexico all the way up the Rockies, through Canada to the territory of Alaska and the continent’s tallest mountain.

In the tundra-covered terrain around Denali (at the time called Mount McKinley), Sheldon was overwhelmed by the abundance of wildlife teeming everywhere: grizzly bears roaming unconcerned by the presence of any other animal, including humans; moose, which Sheldon described as “looking more like prehistoric beasts than any animal we have”; packs of wolves; vast herds of caribou, he said, that “surrounded me like cattle on a cattle ranch”; and the species that had drawn him north in the first place, the distinctive Dall sheep, nearly pure-white animals that he counted by the thousands on the mountainsides.

He made two visits to Denali — one for an entire year — to study the sheep’s habits, collect specimens for the American Museum of Natural History and contemplate what would happen to them (and all the other large animals) when a railroad being built from Anchorage to Fairbanks was completed and commercial hunters suddenly had an easier time getting to the wilderness paradise. He decided the only way to protect the animals was by making the area a national park.

Back in New York City, Sheldon promoted his idea among his fellow members of the elite Boone and Crockett Club, including one its founders, former president Theodore Roosevelt. Nearly 20 years earlier, the club had led the effort for laws that saved the bison in Yellowstone National Park from being hunted to extinction. Now it swung into action again.

At Sheldon’s invitation, Stephen Mather, the first director of the brand-new National Park Service, became a member — and soon endorsed the park plan. Sheldon moved to Washington full time to work on legislation to establish the park, prowling the halls of the Capitol to push it through. On Feb. 26, 1917, he personally delivered it to President Woodrow Wilson for signing.

His only disappointment was that Congress, in creating Mount McKinley National Park, had ignored his repeated pleas to return the mountain — and its new park — to its original name. (In 1980, the park would be nearly tripled in size and its name would be changed to Denali; in 2015, the mountain, too, would revert to its ancient name.)

One hundred years after Sheldon’s campaign, the mountain endures, still thrilling anyone lucky enough to see it in person. But thanks to him, the Boone and Crockett Club, the National Park Service, and many others dedicated to the preservation of wildness in nature, the Dall sheep, bears, wolves, moose and caribou can also still be seen.

“They exist there,” Sheldon wrote, “as a link connecting this life with the life of the past ages, just as the records in the rocks show the records of the past ages there before you.”

Dayton Duncan and Ken Burns are the creators of the PBS documentary The National Parks: America’s Best Idea. In 2009 the National Park Service named them honorary park rangers.