To survive dark winter, Alaskans call on old traditions and learn new techniques.

Life in the isolated wilderness is possible only when people work together.

A select few people choose to live alone in the unforgiving Alaskan wilderness.

At the onset of dark winter, the clock is ticking for Alaskans to brace for what lies ahead.

There are no guarantees for Alaskans during the grim winter in the Arctic.

For Alaskans living off the land, timing is everything.

When confronted with a threat, Alaskans must make quick decisions to survive.

To survive the quickly worsening conditions in the Arctic, Alaskans must finish the tasks that will keep them ahead of winter's wrath; Glenn Villeneuve hunts caribou to keep his family fed for the remainder of winter.

For isolated Alaskans, strenuous labor is just a part of life.

As winter approaches, Alaskans must complete their final tasks before the freeze.

Even the toughest Alaskans sometimes need a helping hand.

On Alaska's merciless tundra, fearless women survive and thrive.

Alaskans living in remote wilderness face the daily challenge of getting enough food to survive.

Alaskans face dangerous predators in the remote wilderness.

Alaska is a land of extremes where a diverse terrain presents unique challenges.

Alaskans struggle to survive the brief, cold and dark days as winter overtakes the land.

Alaskans race to secure resources and ready their camps for the coming dark winter.

In the Arctic, Alaskans fight to secure the bare necessities in order to live and thrive.

In freezing temperatures, Alaskans must build and maintain shelter to survive.

Alaskans travel the flowing rivers to hunt for fresh food and gather supplies.

The thawed waterways of summer allow Alaskans to harvest key resources for their survival.

Each year adventurers make Alaska's mighty Yukon River their home for five weeks. They float downstream on homemade log rafts to sell firewood and other supplies to remote villages. The reality-documentary "Yukon River Run" presents hourlong episodes tracking the progress of various crews. As harsh winter months approach and threaten both safety and success, stakes are heightened as rafters endeavor to cash out and escape from the cold.

Extreme survivalists go head to head in a race across the Alaska wild. Using ingenuity, experience and just the gear they can carry in their packs, the participants have 60 hours to reach the finish point of each leg of the adventure -- the series features 13 legs -- and in addition to navigating treacherous glaciated river valleys, barren ridgelines, and high mountain peaks, the challengers battle hunger, dangerous predators and unpredictable weather. There is no grand prize awaiting each leg's winner, other than the pride of accomplishing a grueling feat. For season three, the 12 competitors are divided equally into four teams -- Military, Endurance, Alaskans and Lower 48.

Patrolling America's largest state is the job of roughly 400 troopers in one of the toughest law enforcement agencies in the nation. Essentially, these cops say, nearly every Alaskan resident is armed and they know how to use their weapons, which makes any scenario a trooper encounters a potentially fatal one. Follow along as the "blue shirt" Alaskan State Troopers police the towns and villages, and the "brown shirt" Alaska Wildlife Troopers enforce regulations covering both commercial and sport fishing and hunting activities.

Wilderness guide and survival instructor Hazen Audel attempts to stay alive in some of the world's most inhospitable places by using centuries-old techniques. Hazen joins tribes in the rainforests of Ecuador, the Kalahari Desert of Namibia, the mountains of western Mongolia, the frozen Arctic of Canada, in equatorial Kenya, and on a remote island in the Pacific Ocean to learn the skills firsthand. He hunts with bows and poisoned arrows, climbs harsh mountains in search of prey, and harvests food beneath shifting sea ice, among other challenges that push him to his limits.

The old Dolly Parton hit "9 to 5" isn't a tune worth humming for the blue-collar pioneers featured in "Filthy Riches." The series spotlights ingenious Americans who skirt a conventional workplace in favor of making a living in the deep rivers, soggy mud flats and wild backwoods of the U.S. Ray Turner, for example, has been catching eels in Delaware for 30 years. He uses a self-made smokehouse in the woods to cook the critters and sell them. Billy Taylor and his sons hunt for prized ginseng root in the Appalachians. Taylor, a fully licensed wild ginseng dealer, promotes sustainability by planting its berries. In Maine, Jim Campbell and Andy Johns make the coastal mud flats their office, as they dig for valuable bloodworms to sell to fishermen. And Greg Dahl and Albert DeSilva are burl hunters. A burl is a hard, unwieldy outgrowth on a tree, usually at the trunk. Burls have value because of the spectacular patterns found in them when cut open.

"It's the end of the world as we know it (and I feel fine)," sang R.E.M.'s Michael Stipe, and it's a proclamation that must resonate with the people profiled in this series. That's because they are all preparing for doomsday, whether it's caused by a natural disaster, a financial collapse or a nuclear winter, and their plan is to outlast and outlive any apocalyptic scenario. The series goes inside America's "prepping" subculture and introduces otherwise ordinary folks who are stockpiling food, water, weapons and whatever else they think is necessary in the event basic services should falter and society turns chaotic and violent. Also, each prepper's plan is reviewed by the consulting firm Practical Preppers, which analyzes its potential effectiveness in case the prepper's worst fears become reality.

The producers of National Geographic Channel's hit series "Life Below Zero" are behind "Port Protection," which profiles individuals trying to survive way above the Lower 48. Surrounded by the North Pacific, Port Protection is a remote community tucked into the northwest corner of Prince of Wales Island, Alaska. The approximately 100 residents who call the rugged, unforgiving land home push the limits of survival, living an isolated and risky existence of self-reliance with no roads, government or law enforcement. However, they think the risk is worth the profound reward: a world of beauty with the security of community without the constraints of bureaucracy.

The daily and subsistence activities of the inhabitants of the most frigid areas on the planet.

Mick Dodge is one with the woods, having left modern conveniences behind 25 years ago to live among the trees, caves and animals in Washington state's Hoh Rain Forest. It's not an easy life by any means -- he sleeps in tree stumps and has no easy access to food -- but each day presents a different adventure, and as the always-barefoot Dodge says, "All I have to do is follow my feet." He's walking in the footsteps of four generations of Dodge men who have called the Olympic Peninsula their home, and because the intensely private former Marine allowed National Geographic access to his world, this time viewers are welcomed to witness the primal life of "The Forrest Gump of Middle Earth."