America's Wild Spaces

The unique landscapes and the animals living in Alaska's Denali National Park and Preserve are spotlighted.

It is one of Earths few landforms visible from space, a World Heritage site, and one of Americas most popular National Park with over nearly five million visitors a year. But at the edge of a chasm, visitors see only a tiny fraction of the Grand Canyons true beauty hidden amidst its stone, its water and its wildlife. Even for scientists it is a place of baffling mysteries. How and when was it actually formed? Why does one of the planets deadliest diseases still endure in the Canyons premier carnivore the majestic mountain lion? What drove one of the largest birds on earth, the California Condor, to the brink of extinction? Why do microscopic colonies of vegetation that bind the desert sand where no other plant can survive take years to regenerate from the pressure of a single human footfall. And finally what of the Canyons earliest human inhabitants? Where did they live? How did they survive? National Geographic Television joins a rare scientific odyssey down the Grand Canyons entire 277-mile length through some of the most treacherous rapids on the planet to try to unlock the mysteries of this great unknown. A select group of scientists and experts will show us a Grand Canyon few outsiders ever see. From the river still cutting through two-billion-year-old stone to the creatures roaming its incomparable back-country, the Grand Canyon still has secrets to tell.

Discover this unique and threatened ecosystem, including carnivorous plants, amphibious birds, fish that breathe air and cacti that grow in water.

It is the driest place in the U.S, with some of the hottest temperatures ever recorded. To forecast how global warming could impact this national park if temperatures rose a few degrees, we set out on an expedition through the Martian-like landscape to document the region's unique creatures. See how some scorpions thrive with a biological "antifreeze" running through their veins, plants live underground without water for months at a time and microorganisms exist by eating rocks.

Far in the Pacific, 250 miles from Honolulu, a hidden wilderness teems with life ... the Northwestern Hawaiian Islands. In 2006, the islands were declared a national monument, in large part because of the area's more than 7,000 marine species. In this special, come aboard a voyage led by scientists from the National Oceanic and Atmospheric Administration who are researching disease-plagued coral reefs, endangered monk seals and the millions of birds nesting in the volcanic islands and atolls.

The stark appearance of Canyonlands conceals life in unexpected places.

For more than half of the U.S. population, the Appalachian Trail is less than a day's drive away. Yet despite its proximity to many major cities like Atlanta and Boston, few truly know the splendor of this national treasure. NGC takes viewers off the beaten track to discover the remote and often unknown corners of the 5-million-step journey.

The Pacific Crest Trail zigzags some 2,650 miles from Mexico to Canada . It cuts through seven national Parks and 24 national forests as it travels through California, Oregon and Washington. Its a trail of ever-changing obstacles - from some of the highest mountain passes in the west to the hottest desert in the country. The two to three hundred hikers who attempt the PCT each year often find out quickly if they have what it takes for the journey ahead.

Glacier National Park in Montana is arguably America’s most stunning landscape, with carved massive glaciers and a melting ice cycle that supports ecosystems of more than 2,000 species of plants and animals. However, the glaciers are disappearing at a rapid rate and may be gone in just 10 years. Following the collapsing of the park's most prominent mountain of ice, National Geographic treks into the Continental Divide to uncover the hidden secrets of this transforming landscape.

Scale the largest granite monolith on Earth, see the tallest waterfall in North America, and touch a giant sequoia, the largest living thing in existence.

Life-changing encounters with the natural world await you off-road and beyond the tourist spots in a Yellowstone you've never seen. Get into the two million untouched acres where the bison and bears roam free.