NARRATOR: THE ROCKIES, ONE OF THE WORLD'S GREATEST MOUNTAIN RANGES.

STRETCHING FOR 3,000 MILES, THEY ARE THE SPINE OF NORTH AMERICA.

SURVIVAL IN THIS UNTAMED WILDERNESS REQUIRES SOMETHING EXCEPTIONAL, BUT FOR THOSE THAT CONQUER THIS WORLD, THE PRIZE IS FREEDOM.

THEY ARE THE MOUNTAINS WHERE SEASONS CAN CHANGE IN MERE HOURS.

IN THIS HIGH LAND OF EXTREMES, TIMING IS EVERYTHING.

SOME SEIZE THEIR MOMENT IN THE WINTER, TACKLING IT HEAD-ON.

OTHERS MAKE THEIR STAND IN THE ROARING HEAT OF SUMMER.

IN THE ROCKIES, THE ONE CONSTANT IS CHANGE, AND SURVIVAL IS NEVER CERTAIN.

ACROSS THE PLANET, THE STRUGGLE TO SURVIVE CONTINUES IN GREAT MOUNTAIN RANGES THAT TOUCH THE SKIES...

HOSTILE, UNFORGIVING WORLDS THAT PUSH LIFE TO ITS LIMITS, WHERE A FEW EXTRAORDINARY ANIMALS AND REMARKABLE PEOPLE DARE TO LIVE IN THE HIGHEST PLACES ON EARTH.

NARRATOR: THE ROCKIES RUN THE LENGTH OF NORTH AMERICA.

THEY RISE UP IN THE SOUTHWEST AND TRAVEL NORTH THROUGH COLORADO, WYOMING, IDAHO, MONTANA, THEN UP INTO CANADA, ALL THE WAY TO THE FROZEN EDGE OF THE YUKON.

LAID HORIZONTALLY, THEY WOULD STRETCH FROM NEW YORK TO CALIFORNIA.

SO MANY MOUNTAINS THAT SOME DON'T EVEN HAVE NAMES.

THIS IS A WORLD WHERE, EVEN TODAY, THERE ARE UNEXPLORED STRETCHES OF WILDERNESS.

ELK HERDS ROAM THE PEAKS, GRIZZLIES RAISE THEIR YOUNG... AND BISON RUN FREE.

THIS IS THE LAST GREAT SANCTUARY OF THE ICONIC ANIMALS OF NORTH AMERICA.

IT'S WINTER, ONLY TEN DEGREES.

THE DAYS ARE GETTING SHORT.

THE PERFECT TIME FOR AN EXTRAORDINARY EVENT TO SHAKE THE ROCKIES.

WYOMING.

THIS IS BIGHORN SHEEP TERRITORY, NORMALLY CALM AND TRANQUIL.

BUT TODAY, A SCENT IS IN THE AIR... [SNORTING] AND IT'S TURNING THE MALES INTO WARRIORS.

IT'S THE MOST IMPORTANT MOMENT IN THEIR YEAR.

IN FACT, ALL THE MALES ARE PICKING UP THE SCENT...

DRAWING IT UP INTO THE ROOF OF THEIR MOUTHS... ANALYZING THE SMELL.

THE FEMALES PRODUCE THIS PERFUME ONLY WHEN THEY'RE IN HEAT, AND THAT'S JUST FOR TWO DAYS; NOT A CHANCE ANY SELF-RESPECTING, RED-BLOODED RAM WANTS TO MISS...

BUT TO GET TO MATE, THEY FIRST HAVE TO FIGHT THE OTHER MALES.

IT BEGINS WITH PUSHING AND SHOVING...

BUT QUICKLY GOES BELOW THE BELT...

GOADING EACH OTHER, SEEING WHO'S THE STRONGEST, WHO'S UP FOR IT.

THIS IS THEIR ONE CHANCE IN THE WHOLE YEAR TO FIND A MATE.

THEY'VE GOT TO TAKE IT.

THE HORNS ALONE CAN WEIGH 30 POUNDS... AS MUCH AS THE REST OF THEIR BONES.

IT'S THE BIGGEST RUMBLE IN THE ROCKIES.

IT ECHOES FOR MILES AROUND THE MOUNTAINS.

[CLAPPING SOUNDS ECHO] CLASHING HORNS... WITH 8 TIMES THE FORCE THAT WOULD FRACTURE A HUMAN SKULL.

OTHER CREATURES WOULD GET BRAIN DAMAGE...

BUT BIGHORNS HAVE A DOUBLE LAYER OF BONE IN THEIR SKULLS TO ABSORB THE IMPACT.

THICK TENDONS JOIN THE SKULL TO THE SPINE TO HELP RECOIL AND PREVENT WHIPLASH.

THE LOSERS ARE LEFT WITH A SORE HEAD.

THEY'LL HAVE TO WAIT A WHOLE YEAR FOR ANOTHER CHANCE TO MATE.

THE VICTORS GET THE FEMALES.

THEY HAVE SEIZED THEIR CHANCE AND WON, AND CHOOSING THAT PERFECT MOMENT IS THE SECRET TO SUCCESS EVERYWHERE IN THE ROCKY MOUNTAINS.

AND THAT'S FOR ONE SIMPLE REASON: THE WEATHER CHANGES QUICKER HERE THAN IN ANY OF THE OTHER GREAT MOUNTAIN RANGES.

THE GREATEST DAILY TEMPERATURE SWING IN THE WORLD WAS RECORDED IN THE ROCKIES, A 100-DEGREE CHANGE IN JUST 24 HOURS.

BUT THE SEASONAL SWING IS EVEN BIGGER.

THE SUMMERS ARE SCORCHING AND DRY.

EVERY YEAR, 700,000 ACRES GO UP IN SMOKE.

TEMPERATURES CAN SOAR UP TO 110 DEGREES.

IN THE WINTER, THE AVALANCHES RIP DOWN AT 80 MILES PER HOUR.

THERE'S 100,000 EVERY YEAR.

TEMPERATURES CAN PLUMMET TO MINUS 40, COLD ENOUGH TO FREEZE THE MERCURY IN A THERMOMETER.

EACH DAY BRINGS DIFFERENT EXTREMES AND CHALLENGES IN THESE EVER-CHANGING ROCKIES.

[WIND HOWLING] BY MID-WINTER, THE WORLD IS FROZEN SOLID.

WATER VAPOR CRYSTALLIZED BY THE FROZEN AIR FORMS DIAMOND DUST.

AT THIS TIME OF YEAR, THERE ARE 16 HOURS OF NIGHT.

THIS DARKNESS BECOMES A STAGE FOR AN INCREDIBLE SPECTACLE.

AS PARTICLES FROM THE SUN HIT THE EARTH'S ATMOSPHERE, THE NORTHERN LIGHTS ILLUMINATE THE ROCKIES.

BUT THIS QUIET BEAUTY IS DECEPTIVE.

THE WEATHER CAN BE BRUTAL.

FREEZING WINDS CAN REACH 200 MILES PER HOUR.

IT CAN SNOW 6 FEET IN A DAY.

FOR MOST, IT IS A TIME OF HARDSHIP AND SUFFERING.

BUT HERE IN THE FAR NORTH OF THE CANADIAN ROCKIES, IT'S THE PERFECT MOMENT FOR ONE ANIMAL THAT HAS MASTERED WINTER SURVIVAL...

THE WOLVERINE.

MOST PEOPLE SPEND A LIFETIME HERE AND NEVER EVEN GLIMPSE ONE.

HE FEEDS ON THE FROZEN CARCASSES OF ANIMALS KILLED BY WINTER... AND PRESERVED IN NATURE'S FREEZER.

HIS NOSE CAN DETECT FOOD BURIED 20 FEET DEEP.

OTHER ANIMALS FOLLOW HIS TRAIL, HOPING THEY CAN STEAL A MEAL.

BUT FROZEN CARCASSES ARE FEW AND FAR BETWEEN.

EACH DAY, HE MUST SCOUR THE MOUNTAINS FOR ANY SCRAPS.

HIS DETERMINATION PAYS OFF.

FROZEN CARCASSES ARE AS HARD AS IRON, BUT HIS SPECIALLY ADAPTED TEETH EASILY TEAR THEM OPEN.

[DISTANT BIRD SQUAWKING] BUT THE RAVENS SOUND THE DINNER BELL... AND IT SUMMONS THE MOUNTAINS' TOP PREDATOR.

[DISTANT WOLF HOWLING] THE WOLVERINE HAS TO ACT FAST.

A HUNGRY WOLF PACK COULD KILL HIM.

MEAL IN HAND, HE DISCREETLY MAKES HIS EXIT.

IT DOESN'T TAKE LONG FOR WOLVES TO DEVOUR A CARCASS.

NOW, WITH THE SCAVENGERS OCCUPIED, THE WOLVERINE IS FREE TO SEIZE ANOTHER MOMENT, FIND ANOTHER MEAL, UNDISTURBED.

HIS PERSISTENCE IS THE SECRET TO SURVIVING THESE SEEMINGLY IMPOSSIBLE ROCKY MOUNTAIN WINTERS.

[DISTANT BIRD SCREECHING] SEIZING OPPORTUNITIES IS CRUCIAL FOR ALL CREATURES THAT LIVE IN THE ROCKIES, AND THAT IS ESPECIALLY TRUE OF ONE UNIQUE ANIMAL...

US.

THE MOUNTAINS CALL TO US, BUT WE ARE NOT BUILT TO LIVE ABOVE THE CLOUDS.

WE, MOST OF ALL, MUST GAUGE THE CONDITIONS PERFECTLY.

FOR THOSE WITH BOTH THE COURAGE AND THE JUDGMENT, THE PRIZE IS THE FREEDOM OF THESE MOUNTAINS.

DESPITE THE DANGERS, FOR SOME PEOPLE THE DRAW OF THE ROCKIES IS SO STRONG, THEY NEED TO GO FURTHER AND HIGHER.

WOMAN: I MEAN, ALL MOUNTAINS HAVE A MOODINESS TO THEM, HAVE A PERSONALITY, BUT THE ROCKIES, ROCKIES MIGHT TAKE THE CAKE.

NARRATOR: HILAREE O'NEILL IS A PROFESSIONAL MOUNTAINEER AND SKIER.

SHE'S CLIMBED EVEREST AND LED EXPEDITIONS TO MOUNTAINS AROUND THE WORLD FOR 15 YEARS.

BUT COLORADO IN THE SOUTHERN ROCKIES IS HER HOME.

HILAREE: IT'S NOT FOR THE BEGINNER.

THEY'RE STEEP MOUNTAINS, THEY'RE RUGGED.

IT KEEPS YOU ON YOUR TOES.

I THINK I COULD SPEND TEN LIFETIMES HERE AND PROBABLY NOT DO EVERYTHING I WOULD LIKE TO DO IN THESE MOUNTAINS.

NARRATOR: THERE IS ONE MOUNTAIN IN PARTICULAR SHE WANTS TO CLIMB, AND NOW, LATE WINTER, IS THE PERFECT MOMENT TO DO IT.

IN THE HEART OF THE SAN JUAN RANGE, MOUNT SNEFFELS IS THE HIGHEST PEAK FOR MILES.

AT JUST 20 MILLION YEARS OLD, IT'S ONE OF THE YOUNGEST MOUNTAINS IN THE ROCKIES AND STILL GROWING FAST.

AT OVER 14,000 FEET HIGH, THE AIR'S 40% THINNER AT THE SUMMIT, AND THE WINDS CAN BLOW OVER 100 MILES PER HOUR...

BUT HILAREE IS DETERMINED TO ATTEMPT IT.

HILAREE: I MEAN, THERE'S, YOU KNOW, LOTS OF CATCHPHRASES ABOUT THE ROCKY MOUNTAINS, AND THE ONE THAT ALWAYS KIND OF STICKS IN MY HEAD IS, YOU KNOW, IF YOU DON'T LIKE THE WEATHER, WAIT 5 MINUTES AND IT'LL CHANGE.

FOR ME, IT MAKES ME WANT TO GO OUT IN THE MOUNTAINS EVERY DAY BECAUSE I THINK IT'S GOING TO BE DIFFERENT EVERY DAY.

AND SOMETIMES, SOMETIMES I THINK THE MOUNTAINS AROUND HERE ARE WARM AND WELCOMING, AND OTHER TIMES YOU'RE LIKE, "GOD, "I JUST HOPE THEY LET ME GO AND LET ME OUT OF THEIR GRASP AND I CAN GO HOME."

[BREATHING HEAVILY] NARRATOR: IT'S A 3,000-FOOT CLIMB TO THE SUMMIT, WITH THE AIR GETTING THINNER AND THE SNOW GETTING DEEPER.

HILAREE: I OFTEN FEEL FRIGHTENED WHEN I'M UP HERE.

I THINK IT'S A GOOD THING TO FEEL FEAR BECAUSE THAT MEANS YOU'RE PUSHING YOURSELF A LITTLE BIT AND THAT MAKES YOU FEEL ALIVE AND... YEAH, I WOULD TAKE THAT ANY DAY.

NARRATOR: THERE'S NO TIME TO REST AT THE SUMMIT.

THE DESCENT IS EVEN MORE CHALLENGING.

FIRST, SHE HAS TO RAPPEL DOWN TO THE START OF THE GULLY.

[WIND HOWLING] EVERY MINUTE, THE WIND IS PICKING UP.

AND FOR HILAREE, THERE IS ONLY ONE WAY DOWN.

THIS STEEP GULLY IS CALLED THE SNAKE, AND IN THESE CONDITIONS, IT IS PARTICULARLY TREACHEROUS.

GULLIES LIKE THIS ARE PRONE TO AVALANCHES, AND HILAREE'S DESCENT IS MAKING THE SNOW INCREASINGLY UNSTABLE.

ONE WRONG MOVE, AND IT WOULD ALL BE OVER.

HILAREE: OH, BOY.

NARRATOR: BUT THERE IS NO TURNING BACK NOW.

[BREATHING HEAVILY] NARRATOR: SHE IS FINALLY FREE FROM THE CLUTCHES OF THE GULLY.

HILAREE: WHOO!

NARRATOR: HILAREE FLIES AT 50 MILES PER HOUR DOWN THE MOUNTAIN, HER INTIMATE KNOWLEDGE OF THE ROCKIES KEEPING HER SAFE.

HILAREE: WHOO!

WHEN I GO AND DO SOMETHING NEW IN THESE MOUNTAINS, IT FEELS PIONEERING IN A MODERN WAY, AND I THINK THAT IS A LOT OF THE SPIRIT OF THE PEOPLE THAT STILL LIVE AROUND THESE MOUNTAINS.

NARRATOR: THE ROCKIES HAVE ALWAYS ATTRACTED PIONEERS.

THOUSANDS FLOCKED HERE IN THE 1800S.

SOME MADE FORTUNES; FOR OTHERS, THEIR TIMING WAS WRONG.

MINING TOWNS ABANDONED AFTER THE GOLD AND SILVER RAN OUT.

HALF A MILLION MINES ARE SCATTERED ACROSS THE WEST.

EARLY MARCH, AND THE LAST SNOW OF WINTER FALLS ON AN ABANDONED HOMESTEAD IN MONTANA...

THE BUILDINGS RECLAIMED BY NATURE.

THESE MULE DEER HAVE BEEN FORCED DOWN FROM THE MOUNTAIN SLOPE TO SHELTER HERE.

IT'S THE LAST PLACE LEFT WITH ANY GRASS TO EAT.

BUT THEY'RE NERVOUS, AND RIGHTLY SO.

SOMETHING HERE IS VERY WRONG.

THE ABANDONED BARNS ARE LITTERED WITH CORPSES OF OTHER DEER.

A PREDATOR IS CLOSE BY... [BIRDS SQUAWKING] ONE WHO KEEPS COMING BACK.

BUT THE MULE DEER FACE A TERRIBLE CHOICE.

IF THEY GO BACK TO THE MOUNTAINTOPS, THEY'LL STARVE.

IF THEY STAY HERE, THEY MAY BE EATEN.

DURING THE DAYLIGHT, THEY'RE SAFE.

BUT AS NIGHT FALLS... [WOOD CREAKS] THE RANCH BECOMES THE REALM OF A PHANTOM KILLER.

UNDER THE CLOAK OF DARKNESS, CATCHING SIGHT OF THIS SILENT PREDATOR IS ALMOST IMPOSSIBLE.

[CLATTERING SOUND] [DISTANT BIRD SCREECHES] IN SOME NATIVE AMERICAN MYTHS, THIS IS A CREATURE OF THE UNDERWORLD... [LOW SNARL] A HARBINGER OF DEATH.

THE MOUNTAIN LION.

SO STRONG, SHE CAN DRAG A KILL SEVERAL TIMES HER OWN BODY WEIGHT IN HER JAWS.

SHE USES THESE BUILDINGS TO HIDE HER KILLS FROM THE PRYING EYES OF OTHER ANIMALS, SO SHE CAN FEED UNNOTICED, UNDISTURBED.

FOR SUCH A POWERFUL ANIMAL, SHE IS SURPRISINGLY SILENT AND LIGHT ON HER FEET.

HUGE PAWS AND A LONG TAIL FOR BALANCE MAKE HER THE BEST AMBUSH PREDATOR IN THE ROCKIES.

THIS DEER IS ENOUGH FOOD TO LAST FOR A WEEK.

SHE'LL RETURN NIGHT AFTER NIGHT TO FEED IN PEACE.

IN SILENCE, SHE SLIPS INTO THE DARK.

THE REST OF THE HERD IS SAFE, UNTIL THE NEXT NIGHT.

[CRICKETS CHIRPING, WIND HOWLING] IT'S THE END OF MARCH.

ACROSS THE ROCKIES, BILLIONS OF TONS OF WATER HAS BEEN LOCKED UP ALL WINTER AS SNOW AND ICE, IN HUGE GLACIERS, IN FROZEN LAKES.

BUT TODAY, FOR THE FIRST TIME THIS YEAR, THE SUN IS IN THE SKY FOR MORE THAN 12 HOURS... AND AT LAST, SPRING HAS ARRIVED.

THE MOUNTAINS ARE WAKING UP, AND THE WATER BEGINS TO FLOW.

3,000 WATERFALLS APPEAR ACROSS THE ROCKIES.

HUNDREDS OF BILLIONS OF GALLONS FLOW DOWN FROM THE MOUNTAINS.

A THOUSAND FROZEN LAKES ARE UNLOCKED AND FILLED WITH MELTWATER.

[BIRDS CHIRPING] THE ROCKIES NOURISH 900 MILLION ACRES ACROSS NORTH AMERICA.

AS THE MOUNTAINS BURST INTO BLOOM, THERE ARE OPPORTUNITIES FOR THOSE WHO CAN SEIZE THEM.

[BISON GRUNTING] AND WITH THIS GLUT OF FOOD COMES NEW BEGINNINGS.

WHAT WAS A DESOLATE LANDSCAPE JUST A FEW SHORT WEEKS AGO IS NOW CROWDED WITH LIFE.

BUT ALL THE ANIMALS ARE MULTIPLYING IN NUMBER.

[ELK BUGLES] THE PREDATOR POPULATIONS ARE ALSO BOOMING.

COYOTE, BLACK BEAR.

EVERYONE'S HUNGRY.

EVERYONE IS LOOKING TO RESTOCK AND REPLENISH AFTER THE BARREN WINTER.

[CHIRPING] IN THE MOUNTAIN MEADOWS OF WYOMING, AN ELK CALF HAS JUST BEEN BORN.

THE TIMING OF HER BIRTH WAS IMPECCABLE: ANY EARLIER, THE FROSTS WOULD HAVE KILLED HER; ANY LATER, SHE WOULD MISS THE SPRING GRASS.

BUT IT'S ALSO THE MOST DANGEROUS TIME, WHEN HUNGRY PREDATORS ARE ALL AROUND.

AS A NEWBORN, HER LEGS ARE TOO WEAK TO HOLD HER WEIGHT.

THE CALF CAN'T RUN TO SAVE HERSELF.

WITH PREDATORS ALWAYS A THREAT, THE CALF HAS TO HIDE.

[SNORTS] HER MOTHER HAS A STRONG SCENT, A BEACON TO PREDATORS.

AS NIGHT FALLS, THE ONLY WAY TO PROTECT HER BABY IS TO LEAVE HER.

THE FIRST NIGHT OF HER LIFE MIGHT BE HER LAST.

[DISTANT HOWLING AND YAPPING] WOLVES, COYOTE, EVEN COUGARS.

ON THAT FIRST NIGHT, THE SOUNDS OF HUNTING ARE ALL AROUND HER.

INSTINCTIVELY, SHE KNOWS TO STAY PERFECTLY STILL.

[OWL HOOTING] [BIRDS CHIRPING] DAWN IS A LONG TIME COMING...

BUT THE FIRST DAYLIGHT TELLS THE TALE.

THE CALF HAS SURVIVED THE NIGHT.

BUT MORNING DOESN'T GUARANTEE SAFETY.

THERE IS A THREAT THAT STALKS THESE CALVES, EVEN BY DAYLIGHT.

DURING THE SPRING, 1/3 OF ALL NEWBORN CALVES ARE KILLED BY ONE UNIQUE PREDATOR.

THIS GRIZZLY BEAR HAS JUST COME OUT OF HIBERNATION AND IS DESPERATE TO EAT.

THE GRIZZLY'S SENSE OF SMELL IS 2,000 TIMES BETTER THAN A HUMAN.

BUT THIS CALF HAS A TRICK TO AVOID BEING SNIFFED OUT.

CLEANED BY HER MOTHER, SHE HAS ALMOST NO SCENT, SO THE BEAR'S NOSE IS NO USE.

BUT GRIZZLIES ARE SMART AND HAVE OTHER TACTICS.

SHE KNOWS, JUST AT THIS TIME OF YEAR, NEWBORNS ARE HIDDEN IN THE SCRUB.

SHE METHODICALLY COMBS THROUGH THE MEADOW.

A PANICKED NEWBORN MAY TRY TO RUN.

THE BABY MUST STAY ABSOLUTELY STILL.

[BEAR SNORTING] THE BEAR AMBLES AWAY, UNAWARE OF THE MEAL THAT WAS UNDER HER NOSE.

THE MOTHER RETURNS TO HER CALF.

EVEN AFTER ONLY ONE DAY, HER LEGS ARE GROWING STRONGER.

HER MOTHER LEADS HER BACK TOWARDS THE MOUNTAINS AND THE SAFETY OF THE HERD.

IN THE ROCKIES, SOMETIMES THE BRAVEST ANIMALS COME IN THE SMALLEST SIZES.

[ELK BUGLES] IT'S LATE SPRING... [BIRDS CHIRPING] AND THE SUN HEATS THE MOUNTAIN ROCKS...

WHICH WARMS THE SURROUNDING AIR, MAKING WINDS WHICH ARE FORCED UP THE VALLEY SIDES.

IT'S THE PERFECT PLACE TO BE... A BIRD.

MAN: I DREAMED ABOUT FLYING WHEN I WAS A KID.

I'VE ALWAYS HAD A FASCINATION AND A CURIOSITY WITH THE FREEDOM THAT BIRDS HAVE.

NARRATOR: JEFF SHAPIRO LIVES IN THE HEART OF THE MONTANA ROCKIES.

THESE CLIFFS OF THE BITTERROOT MOUNTAINS ARE JUST A SHORT RIDE AWAY FROM HIS HOME, HIS FAMILY, AND HIS FALCON.

JEFF: SO THIS IS MY HUNTING PARTNER, SIRIUS.

HE'S A HALF GYR, HALF PEREGRINE TIERCEL.

HE'S A LITTLE OVER A YEAR OLD.

HE'S ALSO PART OF THE FAMILY.

HE'S BECOME QUITE TAME AND DOESN'T MIND THE DOGS OR THE CATS AND CERTAINLY LIKES TO SIT IN THE HOUSE AND WATCH THE WORLD GO BY, AND WHEN WE FLY, HE COMMANDS THE SKY FOR HOURS AT A TIME.

I STILL WATCH HIM FLY A LITTLE BIT SORT OF ALMOST HALF PROUD PARENT, HALF ENVY.

NARRATOR: EVERY OTHER DAY IN THE SPRING AND SUMMER, HE CLIMBS INTO THE MOUNTAINS.

JEFF: I'VE ALWAYS WANTED TO BE IN PLACES THAT WERE BIGGER THAN ME, TO SHOW ME HOW INSIGNIFICANT I AM.

YOU COULD SPEND A LIFETIME IN THE ROCKIES AND NOT SEE ANOTHER PERSON.

THEY JUST GO ON FOR MILES AND MILES AND MILES, AND THAT GIVES ME A FEELING LIKE THERE'S STILL ADVENTURE.

NARRATOR: THE CONDITIONS HAVE TO BE JUST PERFECT.

JEFF: I TRY AND PAY ATTENTION TO WHAT THE BIRDS ARE DOING.

[DISTANT BIRD CHIRPING] I TRY AND PAY ATTENTION TO HOW THE LEAVES ON THE TREES ARE MOVING.

IT ALL GIVES ME INFORMATION THAT WILL HELP ME STAY SAFE.

ONE OF THE MOST IMPORTANT FACTORS IS TIMING.

THE MOMENT YOU CHOOSE IS THE MOST IMPORTANT MOMENT OF YOUR LIFE BECAUSE I'VE COMMITTED.

NARRATOR: THE VALLEY FLOOR IS 3,000 FEET BELOW.

[JEFF EXHALES SHARPLY] JEFF: 3...2...1.

SEE YA.

THE FIRST TIME I STEPPED OFF THE GROUND AND ESCAPED FROM GRAVITY... THAT SENSE OF SPEED, AND YOU'RE CONNECTED TO THE MOUNTAIN, YOU'RE CONNECTED TO THE TERRAIN.

I GUESS IT COULD BE DESCRIBED AS, LIKE, PURE JOY.

[AIR WHOOSHES] [BIRDS CHIRPING] NARRATOR: HARSH SUMMER HAS ARRIVED, AND THE MOUNTAINS ARE NOW BARE.

THROUGHOUT THE ROCKIES, THE MELTING SNOW HAS CREATED TEMPORARY PONDS IN THE MOUNTAIN MEADOWS.

THEY ARE FULL OF LIFE.

BUT IN THE HEAT OF THE SUMMER SUN, THEY WON'T LAST LONG.

IN PONDS LIKE THIS, YOUNG SALAMANDERS ARE GROWING.

JUST 3 INCHES LONG, THEY'RE THE BIGGEST BEASTS IN A TINY KINGDOM WHICH WILL SOON DRY UP AND DISAPPEAR.

THE MANES AROUND THEIR HEADS ARE GILLS, THE FEATHERY FRONDS SOAKING UP THE OXYGEN FROM THE WATER.

THEIR SMALL MOUTHS ARE JUST BIG ENOUGH TO SWALLOW THEIR LUNCH, BUT WITH MICROSCOPIC TEETH, EATING IS A SLOW PROCESS.

AT FIRST, ALL IS WELL.

THE DAYS ARE LONG, THE WEATHER WARM, BUT MOMENTS LIKE THIS ARE FLEETING IN THE ROCKIES.

AS THE SUMMER HEATS UP, THE WATER IN THE POND GOES DOWN.

THE SALAMANDERS START GETTING JUST A LITTLE TOO CLOSE FOR COMFORT.

AS THE POND DRIES UP, SO DOES THE SALAMANDERS' FOOD SUPPLY... [THUNDER] AND THAT CHANGES EVERYTHING.

THIS IS THE BIGGEST SALAMANDER IN THE POND.

HE'S TRANSFORMING INTO SOMETHING MORE... MENACING.

HIS MOUTH HAS GROWN WIDER.

HE HAS GROWN HUNDREDS OF NEW, LONG, NEEDLE-SHARP TEETH TO STOP HIS VICTIMS FROM WRIGGLING AWAY.

THE OTHER SALAMANDERS MAY BE HIS BROTHERS AND SISTERS, BUT THEY ARE STARTING TO LOOK QUITE TASTY.

HE HAS TRANSFORMED INTO A CANNIBAL.

HE'S HAVING HIS FAMILY FOR DINNER.

[BIRD CHIRPING] THE MOUNTAIN SUNSHINE CAUSES THE PONDS TO SHRINK MORE.

THERE'S NO ESCAPE FROM BIG BROTHER.

BUT THE FIGHT'S NOT OVER.

THE OTHER SALAMANDERS ALSO START TO TURN INTO CANNIBALS.

IT'S EAT OR BE EATEN.

EVENTUALLY, IN THIS POND, THERE IS JUST A SINGLE, VERY PLUMP SALAMANDER.

EVERYONE ELSE HAS MYSTERIOUSLY...DISAPPEARED.

BUT IT'S AN EMPTY VICTORY.

THE MOUNTAIN SUN IS TURNING THE POND INTO A PUDDLE.

EVENTUALLY IT WILL DRY OUT COMPLETELY, AND HE TOO WOULD DIE, EXCEPT HE HAS ANOTHER, EVEN GREATER TRICK UP HIS SLEEVE.

THOSE GILLS HAVE DISAPPEARED.

THEY HAVE BEEN REABSORBED INTO HIS BODY.

HE HAS GROWN A PAIR OF LUNGS.

AS THE MOUNTAIN SUN DRIES UP THE VERY LAST OF THE PUDDLE...

THIS MAGICIAN STEPS OUT AND FILLS HIS NEW LUNGS WITH THE WARM MOUNTAIN AIR...

THE ULTIMATE TRANSFORMER.

MIDSUMMER.

BUT EVEN NOW, AUTUMN IS AROUND THE CORNER... AND THE CLOCK IS TICKING TO MAKE THE MOST OF NATURE'S GOLD RUSH.

EVERYONE HAS TO SEIZE THE MOMENT... AND NO ONE IS BETTER AT IT THAN THIS CREATURE... A RUFOUS HUMMINGBIRD.

THEY WEIGH LESS THAN A PENNY, AND WITH A PULSE RATE OF A THOUSAND BEATS PER MINUTE, NO HEART BEATS FASTER.

IN SUMMER, THEY LIVE AT THE NORTHERNMOST PART OF THE ROCKIES, USING THE LONG DAYS TO RAISE THEIR FAMILY.

THESE TINY NEWBORNS ARE THE SIZE OF A SUGAR CUBE, IN A NEST SO LIGHT, IT'S HELD TOGETHER WITH SPIDER SILK.

THEIR BUSY MOTHER FEEDS THEM 60 TIMES A DAY ON A MIX OF REGURGITATED NECTAR AND INSECTS-- HUMMINGBIRD ROCKET FUEL.

SHE CAN RAISE A WHOLE FAMILY IN JUST 18 DAYS.

SOON THERE'S ONLY ONE CHICK LEFT... AND SHE'S RELUCTANT TO FLY THE NEST.

SHE'S STILL GETTING USED TO THE BIG, WIDE WORLD, BUT THE BIGGEST MOMENT OF HER LIFE IS ABOUT TO START.

THE FLOWERS HERE ARE DYING, AND SHE MUST FLY SOUTH IN SEARCH OF FOOD.

SHE FLIES 3,000 MILES FROM THE CANADIAN NORTH, DOWN THE LENGTH OF THE ROCKIES, AND EVENTUALLY TO MEXICO.

LESS THAN A MONTH OLD, TOTALLY ON HER OWN... SHE MUST RACE DOWN THE ROCKIES TO CATCH THE BLOSSOMING FLOWERS, A JOURNEY THAT WILL TAKE HER 3 MONTHS.

SHE CROSSES THE BORDER FROM CANADA TO THE U.S. AND THEN FLIES OVER 5 STATES, OVER MOUNTAIN LAKES, OVER GREAT PEAKS... AND DOWN THROUGH HUGE MOUNTAIN PASSES.

SHE HAS A BRAIN THE SIZE OF A GRAIN OF RICE, BUT SOMEHOW SHE KNOWS EXACTLY WHERE TO GO.

AT THE SOUTHERN END OF THE ROCKIES, THE MOUNTAIN MEADOWS OF COLORADO HAVE A BRIEF MOMENT WHEN EVERY FLOWER IS FULL OF NECTAR.

[BEE BUZZING] IT'S HUMMINGBIRD HEAVEN, AND SHE HAS ARRIVED AT THE PERFECT TIME.

HERE, SHE HAS A PIT STOP TO REFUEL, BUT NOT A MOMENT TO RELAX.

SHE'S OFF AGAIN, FURTHER SOUTH, CHASING THE SUN.

THE TINY HERO OF THE ROCKIES, WITH THE MOST EPIC JOURNEY OF ALL.

SUMMER IS ALL TOO BRIEF IN THE ROCKIES.

NEARLY AS SOON AS IT ARRIVES, IT DISAPPEARS.

THE HOT SUMMER NIGHTS BEGIN TO LENGTHEN, AND ALL THE STARS PUT ON A SPECTACULAR SHOW.

HIGH ABOVE, THE MILKY WAY DRIFTS BY.

[PEOPLE SCREAMING] DOWN BELOW, THE PEOPLE OF THE ROCKIES CELEBRATE THE END OF SUMMER IN COUNTY FAIRS.

THE FIRST FROSTS WILL SOON BE HERE.

FOR MOST, THIS IS A TIME TO RELAX, BUT NOT FOR EVERYBODY.

OLIVER PAKOOTAS IS ABOUT TO FACE THE TOUGHEST RACE IN THE ROCKIES.

MONTHS OF PRACTICE HAVE LED TO THIS ONE MOMENT IN THE HEART OF MONTANA.

[CROWD CHEERING] THE INDIAN RELAY, A ROCKY MOUNTAIN CONTEST OF BRAVERY AND SPLIT-SECOND TIMING.

EACH RIDER MUST COMPLETE 3 LAPS OF THE TRACK.

AT THE END OF EACH LAP, THEY MUST JUMP FROM ONE HORSE TO ANOTHER, AND IT'S ALL DONE BAREBACK.

IT'S A NATIVE AMERICAN COMPETITION DATING BACK AT LEAST 200 YEARS.

DIFFERENT TRIBES COMPETE FOR THE HONORS, AND THE WINNER IS THE FIRST ACROSS THE FINISH LINE.

MAN: KEEP HIM GOING, KEEP HIM GOING.

PUSH HIM ON AND MAKE HIM WORK.

GIVE HIM THE WORK.

HOLY COW.

HA HA!

THAT'S PRETTY GOOD, HUH?

NARRATOR: JUDGING THE PERFECT MOMENT TO JUMP BAREBACK ONTO THE HORSE TAKES OLIVER MONTHS OF TRAINING.

THERE'S A TEAM OF 4 INVOLVED, ALL FAMILY.

BROTHER WINFRED HOLDS THE HORSES IN THE RACE.

SO DOES HIS FATHER JOHN.

FATHER-IN-LAW KERRY IS THE TRAINER.

OLIVER IS THE JOCKEY.

KERRY: YOU ALWAYS REPRESENT WHERE YOU COME FROM, AND THAT'S WHERE GRIZZLY MOUNTAIN COMES FROM.

IT'S THE BIGGEST MOUNTAIN ON OUR RESERVATION.

SO WHEN I REPRESENT MY HOME PEOPLE, SO WHEN I GO ON THE ROAD, I LET PEOPLE KNOW THAT THIS IS WHERE I COME FROM.

THIS IS MY MOUNTAIN, THIS IS OUR MOUNTAIN, MY FAMILY'S MOUNTAIN.

IN ALL THE YEARS SINCE I'VE EVER BEEN A KID, WE'VE ALWAYS HAD HORSES, AND THEY'RE LIKE BROTHERS AND SISTERS TO US.

NARRATOR: THESE HORSES NEED RIGOROUS TRAINING, AND THAT MEANS GETTING DEEP INTO THE MOUNTAINS.

OLIVER: I LIKE TO TAKE THEM IN THE MOUNTAINS.

AND IT'S JUST YOU AND THE HORSE, YOU KNOW, AND YOU ALMOST BECOME ONE.

AND THAT'S HOW IT FEELS, TOO.

IT'S LIKE THEIR LEGS BECOME MY LEGS.

YOU KNOW, A BIRD COULD FLY UP OR A COYOTE COULD RUN BY OR SOMETHING, AND THEN, ONCE THEY GET USED TO THAT, THEN I KNOW THEY'RE READY TO GO DO SOME RELAY RACING.

AND WE DEVELOP A TRUST WITH EACH OTHER OUT THERE WITH THEM THAT YOU CAN'T GET ON A RACETRACK.

NARRATOR: THE INDIAN RELAY IS THE OLDEST SPORT IN THE ROCKIES... AND GREW FROM THE LIFE OF THE NATIVE AMERICAN TRIBES.

[HORSE BREATHING HEAVILY] KERRY: THE HORSE WAS SO IMPORTANT TO US WHEN THEY WERE OUT HUNTING AND GATHERING, AND EVEN WHEN YOU WENT OUT TO CHASE YOUR BUFFALO, I'M SURE YOU HAD TO HAVE A SECOND HORSE OR A THIRD HORSE.

NARRATOR: THE FAMILY HAS DEVELOPED SPECIAL WAYS TO PREPARE THEIR HORSES.

THEIR LOCAL MOUNTAINS HAVE A SALT LAKE THAT COOLS THE HORSES' ACHING MUSCLES AND HEALS ANY CUTS.

[HORSE NICKERS] OLIVER BURNS MOUNTAIN SAGE IN A CEREMONY TO PROTECT HORSE AND RIDER FROM INJURY.

OLIVER: YOU'RE PUTTING A SHIELD OVER YOUR HORSES.

I DON'T KNOW HOW MANY PEOPLE REALLY BELIEVE IN IT, BUT I BELIEVE IN IT.

THAT'S HOW COME WE'RE HERE, IS BECAUSE OUR ANCESTORS DID THE SAME THING.

MAN AND WOMAN: ♪ ...THE LAND OF THE FREE ♪ ♪ AND THE HOME OF THE BRAVE ♪ NARRATOR: IT'S THE DAY OF OLIVER'S BIG RACE.

[RING ANNOUNCER SPEAKING INDISTINCTLY OVER P.A.]

[CROWD CHEERING] NARRATOR: IN THE SHADOW OF THE MOUNTAINS, THE EVENING STARTS WITH A WILD RODEO.

[HORSE NEIGHS] BUT EVERYONE IS WAITING FOR THE MAIN EVENT, THE INDIAN RELAY.

[RING ANNOUNCER SPEAKING INDISTINCTLY OVER P.A.]

OLIVER: WHEN I WALK OUT ONTO THE TRACK, YOU ALMOST-- I GUESS I'D CALL IT GETTING INTO A WARRIOR MODE.

NOTHING ELSE MATTERS IN THE WORLD.

[HORSE WHINNIES] WHEN YOU'RE BAREBACK, HORSES CAN FEEL YOUR HEARTBEAT.

SO IF I'M STAYING CALM, YOU KNOW, THEY KNOW THERE AIN'T NOTHING TO WORRY ABOUT.

[HEART BEATING] NARRATOR: OLIVER IS PRIMED.

THE OTHER HORSE IS READY.

HIS MOMENT HAS COME.

[CROWD CHEERING AND WHISTLING] OLIVER: YOU ALMOST GET THIS SENSE OF INVINCIBILITY.

ALL THAT MATTERS IS THAT NEXT 3 MINUTES... [HORSE WHINNIES] ALMOST LIKE YOU'RE GOING TO GO INTO BATTLE.

[HORSE WHINNIES] [CROWD CHEERING] NARRATOR: OLIVER IS FIRST ACROSS THE FINISH LINE.

A ROCKY MOUNTAIN TRADITION PASSED DOWN THROUGH SO MANY GENERATIONS, ALL PLAYED OUT IN JUST ONE MOMENT AND TIMED TO PERFECTION.

[CHEERING FADES] [BIRDS CHIRPING] OLIVER IS BACK IN THE LAND BELONGING TO HIS TRIBE.

THERE ARE ONLY A FEW LAST MOMENTS TO TAKE HIS HORSE INTO THE MOUNTAINS BEFORE THE FIRST FLURRIES OF SNOW BEGIN TO FALL.

SUDDENLY, AS IF WITH THE FLICK OF A SWITCH, AUTUMN IS HERE.

THE NIGHTS ARE DRAWING IN, CLOAKING THE ROCKIES IN 14 LONG HOURS OF DARKNESS EACH DAY.

FROM HERE ON IN, THE TEMPERATURE WILL DROP DAILY.

THE WATER THAT GAVE WAY TO SO MUCH LIFE WILL FREEZE AGAIN.

AS LIFE GETS HARSHER...

THE FIGHT FOR SURVIVAL GETS TOUGHER.

[SNORTS] BUT THAT WILL NOT STOP THOSE WHO CALL THESE MOUNTAINS HOME.

THOSE WITH THE KNOW-HOW WILL SEIZE THEIR MOMENT ONCE AGAIN AND THRIVE IN THESE EVER-CHANGING ROCKY MOUNTAINS.

"KINGDOMS OF THE SKY" IS AVAILABLE ON BLU-RAY AND DVD.

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