In the heat of August 1924, three men sat near the scenic saddle of Logan Pass, high in the wilds of Glacier National Park. They were squabbling, trying to settle an argument that would define once and for all the look of America’s national parks.

The veteran road engineer imagined a route to the pass that tracked up 15 switchbacks, a zipper cut deep into rocky cliffs.

The greenhorn landscape architect was dismayed, saying it would “look like miners had been there.” He wanted a lighter touch, a single switchback with the rest of the road pinned delicately to Glacier’s soaring Garden Wall.

Too expensive, the engineer countered. Too difficult. Not practical.

The third man on the mountain pass was Stephen Mather, first-ever director of the National Park Service. As the two men bickered, Mather eyed them carefully, glanced at their horses and finally rode off alone. Two days later, Mather made his decision: efficiency be damned. A park as fine as Glacier should not be marred by unsightly switchbacks.

Going-to-the-Sun Road marked the first time the landscape architect’s appreciation for nature’s beauty had overruled the engineer’s practicality. No longer were national park roads simple roads; from that moment on, they were part of the vision.

Vision is a particularly powerful word, and visionaries such as Mather are particularly powerful people. The term conjures an inspired farsightedness, a wisdom coupled with intuition and judgement. At its human best, vision is hope and imagination and the promise of something better than we are today.

Of course, vision without action is just a dream. The real work is in the doing.

We are fortunate to have inherited a wild and wonderful world imagined by doers. Without their vision and their action, there would be gold mines and dams in the Paradise Valley, no wolves in Yellowstone, no grizzly bears in Grand Teton. In fact, there would be no Yellowstone or Grand Teton at all.

After helping to establish the Park Service, Mather co-founded the National Parks Conservation Association (NPCA) because he knew parks would need not just an agency but also an independent advocate. And for 100 years, since 1919, that’s exactly what NPCA has been doing.

Two weeks ago, NPCA gathered people from throughout the northern Rockies for a centennial moment – an opportunity to look back and imagine ahead. We invited business owners and county commissioners, gateway community leaders and tribal leaders. State officials, tourism officials, wildlife officials, park officials. academics, ranchers, hunters, writers and teachers.

These are the modern-day Mathers, the people bringing imagination and tenacity to building a better world. Because here’s the thing about vision: Despite the narrow practicalities of engineers, despite the bluster of vested interests, despite the controversy of predators, somehow the hopeful beauty of an inspiring idea can help us imagine our way to a better world.

That’s what parks do. That’s the birthright we have inherited, and that’s the legacy NPCA works to steward. Our parks are cultural touchstones as much as ecological wonders, places that reflect the core of who we are and what we value. They are a responsibility, yes, and also an endless opportunity. They are the wild beating heart of tomorrow; the essential center of our ecologies and our economies.

One thing they are not, however, is an accident. Our parks were not created, designed or kept whole by benign neglect. Rather, they are a constant choice, a leap of faith, a marriage of inspiration and perspiration. And they are worth the work.

Today’s challenges — climate change, tourism, water wars, wildlife extinctions — are mind-bogglingly big. But they are not unsolvable. They are the work of our generation, and our parks and their origin stories provide us a template for getting there. Hopefully, with a powerful vision and many hands, between us we can build an elegant trail to the summit that is worthy not just of the destination, but of the generations yet to travel here. Join us at www.npca.org/100

Betsy Buffington is the Northern Rockies regional director for the National Parks Conservation Association.