It has been more than eight decades since Canadians and Americans came together to forge Waterton-Glacier International Peace Park, the world's first cross-border park dedicated to protect unique ecosystems that flourish where the prairie rises up to the crooked spine of the Rocky Mountains. That concept -- an international park -- is gaining renewed attention, both due to last fall's World Parks Congress, as well as next year's centennial of the National Park Service in the United States.

There's a success story to be told about bison at Yellowstone National Park. Though there's controversy over how the population is managed, there was a time when it was feared these iconic animals would be lost.

The 2013 Rim Fire was the largest forest fire in California history, and the largest fire in Yosemite history. Burning 400 square miles, the speed and size of the fire was unprecedented. As these unnaturally large fires become more commonplace due to previous fire suppression and climate change, Yosemite National Park is seeing the benefits of carefully allowing smaller, controlled fires on the landscape.

With over half the world's geysers, Yellowstone National Park offers tremendous opportunities to see these geologic wonders in action. Explore the mechanics of geysers, their role in the park's history and what they teach us about the world in which we live. Produced by Steven Bumgardner.