Rocky Mountain National Park shines after a winter snow.

(Photo: Courtesy of Chris Wheeler, Great Divide Pictures)

From forbidding granite canyons to the fragile sandstone that housed an ancestral nation, Colorado's national parks have been shaped by natural forces -- and by people. 

Filmmaker Chris Wheeler spent almost three years making "Heart of the World: Colorado's National Parks." The film explores the the beauty and history of the Black Canyon of the Gunnison, the Great Sand Dunes National Park and Preserve, Rocky Mountain National Park and Mesa Verde, along with Colorado National Monument.

The first two segments air on Rocky Mountain PBS, Channel 6, tonight starting at 8 p.m. Thursday. The third segment airs next Thursday night, April 14, also at 8 p.m.

The entire documentary will air on Colorado Public Television, Channel 12, next Wednesday, April 13, from 7 p.m. to 10 p.m. Watch a trailer for the film here. Listen to the conversation by clicking the audio link above. Read edited excerpts from the conversation below.

The sun sets over the Great National Sand Dunes and Preserve.

(Photo: Courtesy of Chris Wheeler, Great Divide Pictures)

Did you know?

  • Great Sand Dunes National Parkcontain 9 billion cubic feet of sand.
  • The first explorers down the Gunnison River through the Black Canyon were on inflatable mattresses.
  • The founder of Colorado National Monument, John Otto, called it "the heart of the world."

At one point, Wheeler's lens rests on an emotional park visitor, typical of many, who was clearly moved by what he saw and says, "When I see things like this this, I'm really glad to be alive."

Wheeler on why so many people well up with tears:

"I think that's a testament of the power of these places. I think in the film we wanted to tell the story of the parks of course. But I think we also wanted to show just the, you know the immense power and and an amazing effect these these places have on human beings."
 
Why he documented some of the already most-visited spots in the state:

Wheeler: "I think one of the reasons is this is the 100-year anniversary of the National Park Service, so that was one reason to do it now. But it's a timeless story, I think. Like many Coloradans, I love he place that I live, and I had an opportunity to tell the story of what I think is the very best of Colorado: its national parks. ... I think the thing that struck me more than anything though is the diversity of these places. These five parks are amazingly diverse. They're also incredibly different [from each other]. I don't think there's another state in the country that can boast the diverse national parks... the Sand Dunes for instance, and Rocky Mountain National Park."

On why he mostly worked alone in the field:

Wheeler: "I was just coming off of a project that was massive. It was on the American Civil War, and that was very much a film about death and chaos, and war. You know, I thought it would really be great to do something maybe more more solo, that was on -- really looked at -- life and peace rather than war. ... I actually enjoyed the solitude."

Why it was so hard to film in Rocky Mountain National Park:

Wheeler: "We had to do a lot of hiking and you're just exposed to a lot of external factors. I mean, when you get above tree line the wind could be whipping -- I think there were times where I was probably in the midst of 70 mph wind. It's very hard to do, filming in those conditions. But on the other hand, that is a part of that park's  story, so that's what we tried to capture. The lightning, for instance, which has proved deadly in that park, something you have to certainly watch for above tree line ... you know it's that fine line: You want to capture the drama. ... standing up there with a tripod and the camera above tree line is probably not the smartest thing to do during a storm."

The Black Canyon of the Gunnison.

(Courtesy of Chris Wheeler, Great Divide Pictures)

The Black Canyon of the Gunnison's relationship to the Andromeda galaxy:

There's a scene where people are outside at night and there's an image of the Andromeda galaxy, 2.5 million light years away, a member of the Rocky Mountain Astronomical Society puts the two together for the audience: "The light we will see tonight from the Andromeda galaxy started on its way to us at about the same time that the major erosion was taking place here."

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