America's National Parks, One at a Time

Bryce Canyon isn't really a canyon -- it's a retreating plateau edge covered in thousands of hoodoo spires. We cover why frost wedging, not flowing water, is the primary sculptor here, how the uneven Claron Formation rock gives hoodoos their lumpy...

Arches National Park holds the highest concentration of natural stone arches on Earth, shaped by an ancient buried salt layer and slow freeze-thaw erosion rather than wind. We cover how Delicate Arch formed, why Wall Arch collapsed overnight in 2008,...

Glacier National Park had about 80 glaciers in 1910; fewer than 30 remain today. We cover why most of the dramatic valleys and peaks were actually carved by ice age glaciers gone 12,000 years ago, how fast today's smaller glaciers like Grinnell are...

The Everglades isn't a swamp -- it's a slow-moving, 60-mile-wide river of grass. We cover why alligators and crocodiles coexist here and nowhere else on Earth, the triple UN designation this park holds, and the multi-billion-dollar restoration effort...

Denali rises higher base-to-peak than Everest and generates some of the harshest weather on the continent. We cover the mountain's two competing height records, the century-long naming controversy finally resolved in 2015, and why Denali is the only...