NARRATOR: ONE RIVER FLOWS FURTHER THAN ANY OTHER ON EARTH.

THE NILE.

THE LONGEST RIVER IN THE WORLD TRAVELS MORE THAN 4,000 MILES NORTH, ALL THE WAY FROM THE EQUATOR TO THE MEDITERRANEAN.

A RIVER THAT GAVE RISE TO GREAT CIVILIZATIONS... AND BRINGS LIFE TO THE WORLD'S HOTTEST CONTINENT.

THE NILE'S RECORD-BREAKING LENGTH TAKES IT THROUGH MORE ASTONISHING WORLDS THAN ANY OTHER.

A MIRACULOUS, CHANGING RIVER THAT BREATHES LIFE INTO ALL IT TOUCHES.

SHAPING THE FACE OF AFRICA.

EARTH'S RIVERS OF LIFE MAKE EXTRAORDINARY JOURNEYS.

CARVING THROUGH CONTINENTS.

NURTURING GREAT CIVILIZATIONS.

FEEDING AND CONNECTING LIFE ACROSS OUR WORLD.

THESE RIVERS ARE THE LIFEBLOOD OF PLANET EARTH.

NARRATOR: THE NILE.

THE VERY NAME CONJURES UP IMAGES OF PHARAOHS, DESERTS, AND THE GLORIES OF ANCIENT EGYPT.

BUT THIS ICONIC RIVER ACTUALLY STARTS ITS 4,000-MILE JOURNEY IN A REMOTE TROPICAL WORLD, FAR FROM THE PYRAMIDS AND SPHINXES.

AN EQUATORIAL LAND, FULL OF TOWERING MOUNTAINS AND COLOSSAL PEAKS.

THE RWENZORIS.

NESTLED BETWEEN CONGO AND UGANDA, THIS IS THE HIGHEST AND MOST SPECTACULAR SOURCE OF THE NILE.

TORRENTS OF RAIN AND SNOW MELT TUMBLE OFF PEAKS OVER 15,000 FEET HIGH.

THIS WATER WILL EVENTUALLY REACH THE MEDITERRANEAN SEA BUT FIRST MUST EMBARK ON AN INCREDIBLE VOYAGE ACROSS AFRICA.

AS THE HEADWATERS OF THE NILE START TO GATHER, THEY MOVE ISLANDS OF FLOATING PAPYRUS, CREATING A DANCING WATER GARDEN.

THIS SHIFTING WORLD IS PROBLEMATIC FOR THOSE TRYING TO MAKE THEIR HOME HERE.

THIS IS ONLY ONE OF 150 SHOEBILL STORKS LEFT IN UGANDA.

AS THE LANDSCAPE MOVES AROUND HIM, SPOTTING FISH IS A STRUGGLE.

NOSE DIVES OFTEN RESULT IN JUST A MOUTHFUL OF LEAVES.

BUT IN THIS CONFUSING WORLD, HE'S ABLE TO FIND HELP FROM AN UNEXPECTED SOURCE.

HE'S ON THE SEARCH FOR ONE OF NATURE'S BIGGEST BULLDOZERS.

BY FOLLOWING IN ITS GIANT FOOTSTEPS...

THE SHOEBILL IS ABLE TO SPOT FISH IN THE CHANNELS THE HIPPOPOTAMUS LEAVES BEHIND.

IN THE NILE'S EVER-CHANGING WATERS, THERE ARE ALWAYS OPPORTUNITIES FOR THOSE RESOURCEFUL ENOUGH TO FIND THEM.

AS ALL THESE EARLY STREAMS OF THE NILE START TO POOL TOGETHER...

THEY CREATE A WORLD OF EQUATORIAL LAKES IN THE HEART OF AFRICA.

THE GREATEST OF ALL IS CALLED VICTORIA.

THE LARGEST TROPICAL LAKE IN THE WORLD.

EACH DROP OF WATER SPENDS AN AVERAGE OF 23 YEARS HERE BEFORE CONTINUING ITS JOURNEY.

HERE IN NOVEMBER, THE NEW MOON TRIGGERS ONE OF THE NILE'S MOST REMARKABLE EVENTS.

AND LOCAL BOATMAN CHARLES TINKIMWEMURA WILL BE READY.

TINKIMWEMURA: MANY PEOPLE DIE ON THIS LAKE.

IT'S SO DANGEROUS.

NARRATOR: AS THE LAKE IS PLUNGED INTO DARKNESS... LANTERNS ARE THE ONLY SOURCE OF LIGHT.

BUT CHARLES ISN'T ALONE OUT HERE.

30,000 OTHER BOATS ARE ALSO OUT ON THE LAKE.

MANY OF THEIR OCCUPANTS CAN'T SWIM, SO, BEING ON THE WATER IN THE PITCH BLACK IS A RISK.

BUT THE WATER IS STILL AND THE FISHERMEN HOPEFUL.

BECAUSE TONIGHT, LAKE FLIES WILL EMERGE FROM THE DEPTHS AND GATHER AROUND THE LIGHTS... [FLIES BUZZING] BECOMING THE PERFECT LURE FOR HUNGRY FISH.

THIS IS WHAT THE FISHERMEN HAVE BEEN WAITING FOR.

THE CATCH OF THE YEAR.

AS CHARLES PADDLES HOME TRIUMPHANT, HIS BOAT HEAVY WITH FISH, THE AIR IS THICK WITH BILLIONS OF FLIES.

THESE SWARMS OF A BIBLICAL SCALE SWEEP ACROSS THE LAKE...

SPIRALING 300 FEET HIGH IN A MATING DANCE.

BUT THESE OFFERINGS FROM THE NILE'S WATERS ARE NOT ONLY WELCOMED BY FISHERMEN, BUT ALSO BY THE ISLANDERS.

WITHIN A FEW HOURS, THESE FLIES WILL DIE.

SO, THE GAME IS ON TO CATCH AS MANY AS POSSIBLE.

EACH OF THESE FLY BURGERS HAS 5 TIMES MORE PROTEIN THAN A HAMBURGER.

UNDERSTANDING THE CHANGING CYCLES OF THE LAKE ARE THE KEY TO SURVIVAL HERE.

BUT AS THE NILE'S WATERS FLOW OUT OF THIS RESERVOIR, SURVIVAL ON THE NEXT STEP OF ITS JOURNEY WILL DEMAND A VERY DIFFERENT SKILL.

ALL OF LAKE VICTORIA'S WATER LEAVES BY A SINGLE EXIT CHANNEL IN UGANDA.

AND SO IS BORN A THUNDERING RIVER.

THIS IS THE APTLY NAMED WHITE NILE.

MOST STAY AWAY FROM ITS RAPIDS, BUT FOR LOCAL MOM AMINA TAYONA, THE TURBULENT WATER PROVIDES AN UNEXPECTED LIFELINE.

SHE LEFT SCHOOL AT 16 TO WORK ON HER SMALL PATCH OF LAND, BUT A CHANCE MEETING CHANGED HER LIFE FOREVER.

TAYONA: AS I WAS IN THE VILLAGE, I SAW A WHITE GUY FROM THE U.K. AND I WAS LIKE, "CAN YOU TAKE ME KAYAKING?"

AND HE WAS LIKE, "SURE."

AND THAT TIME I DIDN'T KNOW ANYTHING ABOUT KAYAKING.

NARRATOR: WITHIN 6 MONTHS, SHE GOT A JOB AS A KAYAK GUIDE, NOW ABLE TO SUPPORT HER FAMILY OF 10.

AND TODAY, SHE IS TRYING TO PROVE HER SKILLS IN AN INTERNATIONAL ENDURANCE RACE AGAINST WORLD-CLASS ATHLETES IN A BORROWED KAYAK AND USING A HOMEMADE PADDLE.

[HORN HONKS] 6 BILLION GALLONS OF WATER CASCADE DOWN THESE STEEP CHANNELS EACH DAY.

AND IT'S NOT LONG BEFORE AMINA FALLS PREY TO THE NILE'S POWER.

TAYONA: IF YOU GO UPSIDE DOWN, IT'S HARD SOMETIMES, BECAUSE MY BREATH IS A BIT SHORT.

30 SECONDS AND IT'S FINISHED.

NARRATOR: BUT AMINA IS NOTHING IF NOT DETERMINED.

TAYONA: BECAUSE I'M BORN FROM THE NILE, NOTHING I CAN'T DO.

NARRATOR: IT'S SUCH A DANGEROUS STRETCH OF THE RIVER THAT COMPETITORS HAVE TO STAY IN PAIRS FOR SAFETY.

TAYONA: WHEN WE ARE RACING, WE NEED TO BE CLOSE, CLOSE, SO THAT YOU CAN SAVE YOUR FRIEND IF SOMETHING HAPPENS.

NARRATOR: ESPECIALLY WHEN PASSING THROUGH THE NILE'S ITANDA FALLS.

CLASS 6 RAPIDS--THE HARDEST POSSIBLE GRADE OF WHITE WATER IN THE WORLD.

TAYONA: ITANDA CAN MAKE ME NERVOUS BECAUSE IT'S A GRADE 6--IT'S REALLY BIG AND YOU ARE LIKE, OH, MY GOD, HOW AM I GOING TO DO THIS?

[LAUGHS] NARRATOR: EXHAUSTED AFTER 3 HOURS OF PADDLING, AMINA IS APPROACHING THE FINISH.

TAYONA: AMINA, GO.

AMINA, OUR ENEMIES ARE CLOSER.

WE GO, WE GO.

THEY ARE COMING.

GO HARD, GO HARD.

NARRATOR: AMINA AND HER PARTNER ARE THE FIRST WOMEN'S TEAM ACROSS THE FINISH LINE.

TAYONA: THE MOST TIME WHEN I AM HAPPY WHEN I AM WINNING.

WHEN I'M LIKE THE CHAMPION.

THAT'S WHY I'M CALLED THE QUEEN OF THE NILE.

NARRATOR: BUT BEYOND THESE TREACHEROUS RAPIDS, THIS POWERFUL RIVER CREATES A BARRIER THAT EVEN AMINA CAN'T PASS.

THE 160-FOOT-WIDE RIVER IS SQUEEZED THROUGH A 23-FOOT GAP.

THIS IS MURCHISON FALLS.

ONE OF THE MOST POWERFUL WATERFALLS IN THE WORLD.

A GATEWAY INTO A WILD, UNTAMED WORLD.

NOW 250 MILES NORTH FROM ITS EQUATORIAL BEGINNINGS, THE NILE ENTERS A SAVANNAH LAND RULED BY GIANTS.

[HIPPOS GROWLING] CROCODILES, UP TO 18 FEET LONG, AWAIT CARRION WASHED OVER THE FALLS.

THE NILE IS NOW THE ONLY WATER FOR MILES AROUND.

A MAGNET FOR AFRICA'S BIGGEST GAME.

[ELEPHANT TRUMPETS] THIS CROCODILE MOTHER HAS FOUND A SECLUDED PLACE ON SHORE TO BURY HER EGGS.

FOR TWO WHOLE MONTHS, SHE HAS DEVOTEDLY WATCHED OVER THEM, KEEPING THEM SAFE.

BUT SHE CANNOT HIDE THEIR SCENT.

A NILE MONITOR LIZARD IS DANGEROUSLY CLOSE TO HER EGGS.

THE WORST POSSIBLE NEWS FOR A CROCODILE MOTHER.

OUT OF THE WATER, THE MONITOR IS THE FASTER OF THE TWO REPTILES...AND KNOWS IT.

IT ALSO SEEMS AWARE OF THE CROCODILES' ACHILLES HEEL.

ON LAND, CROCODILES CAN DIE FROM HEAT EXHAUSTION... LEAVING THE MOTHER WITH A TERRIBLE DILEMMA.

THE WATER IS THE ONLY PLACE WHERE SHE CAN LOWER HER BODY TEMPERATURE TO SAFE LEVELS.

BUT IF SHE LETS HER GUARD DOWN NOW, HER BROOD WILL BE DEVOURED.

THE MOTHER'S BODY IS REACHING LETHALLY HIGH TEMPERATURES.

SHE FINALLY HAS TO CHOOSE HER OWN LIFE OVER THAT OF HER YOUNG.

ALL SHE CAN DO IS HOPE THAT THE MONITORS WON'T FINISH ALL 60 OF HER EGGS.

BUT THE NILE'S CROWDED BANKS ARE HOME TO OTHER WILY PREDATORS.

BABOONS SAUNTER IN TO TAKE THE EASY PICKINGS FROM THE UNDEFENDED NEST.

TAKING EVERY LAST EGG.

FIGHTING WITH THE MONITORS OVER THE REMAINS.

ONLY 2% OF NILE CROCODILE EGGS REACH ADULTHOOD... DUE TO THE GAUNTLET OF HUNGRY ANIMALS DRAWN TOGETHER BY THE RIVER.

WITH SO MUCH ACTION ON THE RIVER, THIS IS A PERFECT PLACE FOR A GAME LODGE.

THIS WAS ONCE THE EXTRAVAGANT COUNTRY HOME OF BRUTAL DICTATOR IDI AMIN.

KNOWN AS THE BUTCHER OF UGANDA, AMIN ORDERED THE DEATHS OF 300,000 PEOPLE... AND HOSTED HUNTING PARTIES DEVASTATING TO UGANDA'S WILDLIFE.

BUT SINCE HIS EXILE IN 1979, THIS LODGE HAS SUPPOSEDLY BEEN UNINHABITED.

BUT LOCAL RUMORS SUGGEST THAT IT NOW HOSTS NEW GUESTS.

FILMED FOR THE VERY FIRST TIME, THESE RUINS ARE STARTING TO REVEAL THEIR SECRETS.

A FAMILY OF WARTHOGS HAS TAKEN UP RESIDENCE IN WHAT WAS ONCE THE KITCHEN...

WHILE A BABOON CLAN HAS OPTED FOR A ROOM WITH A NILE VIEW.

[ANIMAL BARKING] THE SAVANNAH CREATURES SEEM TO BE MAKING THEMSELVES A HOME HERE.

[ANIMAL BARKING] AS NIGHT CLOSES IN...

THE WARTHOG FAMILY SNUGGLES UP...

WHILE OTHERS ARE JUST WAKING.

A PAIR OF PORCUPINES ARE DENNING UNDER THE STAIRS...

WHILE SOME BATS ARE RECONSIDERING THEIR CHOICE OF ROOMMATE.

THE MOST EXCLUSIVE NAME ON THE GUEST LIST IS THE EXTREMELY RARE PANGOLIN.

AT NIGHT, IT'S BEST TO STICK CLOSE TO MOM.

BUT ONE OF THE PIGLETS IS BOLDER AND MORE CURIOUS THAN THE OTHERS.

AND THIS IS NO PLACE TO BE OUT ALONE.

IN THIS MAZE OF ROOMS, IT'S EASY TO LOSE YOUR WAY.

LOST AND ALONE, THE PIGLET IS EXHAUSTED.

[PIGLET SQUEALING] A PIGLET IS USUALLY AN IRRESISTIBLE SNACK FOR A LEOPARD...

BUT REMARKABLY, THE LEOPARD LEAVES IT ALONE, UNHARMED.

INSIDE THESE WALLS, THERE SEEMS TO BE A RULE AGAINST EATING THE OTHER GUESTS.

[WARTHOG GROWLING] AS MOM CALLS IN HER PIGLETS, MORE FAMILIES BEGIN TO SHOW THEMSELVES.

BIG AND SMALL, NILE CREATURES HAVE ADAPTED TO MAKE THE MOST OUT OF THIS RIVERSIDE RESIDENCE, AND THE ABANDONED HOTEL IS TRANSFORMED FROM A HARBORER OF DARK HISTORY INTO AN UNLIKELY PARADISE FOR WILDLIFE.

AS THE NILE LEAVES THE SAVANNAH, IT COMES TO A PIVOTAL POINT IN ITS VOYAGE.

IN SOUTH SUDAN, 800 MILES FROM THE NILE'S HEADWATERS, THE LAND FLATTENS AND THE RIVER TRANSFORMS INTO A SWAMP THE SIZE OF NEW MEXICO.

THIS IS THE SUDD-- ARABIC FOR "BARRIER."

IT'S THIS SEA OF PLANTS THAT PREVENTED EARLY EXPLORERS FROM FINDING THE NILE'S SOURCE.

IN THIS FLOATING WORLD, YOU HAVE TO LEARN TO NAVIGATE THE MAZE.

FOR ONE ANIMAL IN PARTICULAR, THE NILE SWAMPS ARE A HAVEN.

[ELEPHANT TRUMPETS] NILE ELEPHANTS SEEM TO SPEND MORE TIME IN THE WATER THAN OUT OF IT.

BUT FIRST, THEY NEED TO LEARN HOW TO SWIM.

AND BABY SWIMMING CLASSES ARE A FAMILY OCCASION.

[ELEPHANT TRUMPETS] A MOTHER ENCOURAGES HER YOUNGSTER INTO THE WATER...

WHILE THE BIGGEST OF THE FAMILY GO FIRST, ACTING AS LIFEGUARDS.

[HIPPO GROWLING] WITH LITTLE LEGS, THE YOUNGSTER IS QUICKLY OUT OF HER DEPTH AND TRYING TO TREAD WATER.

HER FAMILY CLOSE IN AROUND HER, SURPRISINGLY BUOYANT FOR THEIR GREAT SIZE.

THEY HELP TO KEEP HER AFLOAT...

ALLOWING THE BABY TO PRACTICE HER TRUNK CONTROL.

TRUNKS CONTAIN 40,000 MUSCLES, MAKING THEM EXCELLENT SNORKELS.

ONCE SHE MASTERS THE SKILL... SHE WILL BE ABLE TO FREELY ROAM ACROSS GREAT AREAS, USING THE NILE AS A HIGHWAY.

[ELEPHANT TRUMPETS] FEW ANIMALS CELEBRATE THE NILE'S WATERS LIKE THE ELEPHANT.

[ELEPHANT GROWLING] THIS MAY BE A SAFE REFUGE FOR SOME, BUT FOR THE NILE ITSELF, TRANSFORMATION INTO AN ENORMOUS, SPRAWLING WETLAND MEANS ITS WATERS DRASTICALLY EVAPORATE.

HERE, OVER HALF OF THE NILE'S WATERS ARE LOST TO THE SCORCHING SUN.

AND IT STILL HAS 2,000 MILES TO GO AND A MIGHTY DESERT TO CROSS BEFORE IT REACHES THE MEDITERRANEAN SEA...

BUT HELP IS ON ITS WAY.

HUNDREDS OF MILES AWAY, STORMS IN THE ETHIOPIAN HIGHLANDS FILL THE NILE'S GREATEST TRIBUTARY...

THE BLUE NILE.

THIS REGION IS KNOWN AS AFRICA'S WATER TOWER.

THESE FERTILE WATERS WILL TRAVEL 1,000 MILES TO EVENTUALLY JOIN UP WITH AND REVITALIZE THE WHITE NILE.

SOME BELIEVE THAT THE BLUE NILE IS THE BIBLICAL RIVER THAT FLOWED OUT FROM THE GARDEN OF EDEN.

AND SOME OF THE WORLD'S OLDEST CHRISTIAN COMMUNITIES ARE FOUND ON ITS BANKS.

IN THE ANCIENT CITY OF GONDAR, THE ETHIOPIAN WATERS OF THE BLUE NILE ARE DIVERTED FOR A RELIGIOUS CEREMONY... AN ANNUAL EVENT CALLED TIMKET.

[WOMEN TRILLING] A CHRISTIAN FESTIVAL WHERE THOUSANDS GATHER TO BE BAPTIZED IN THE NILE'S SACRED WATERS.

FOR THOMAS ALAMU, THIS IS THE MOST IMPORTANT EVENT OF THE YEAR.

ALAMU: THE FEELING AFTER BEING BAPTIZED IS REALLY MORE THAN ANYTHING.

I HAVE NO WORDS EVEN TO EXPLAIN THE FEELINGS THAT I WOULD HAVE.

NARRATOR: BEFORE HIS BAPTISM TAKES PLACE, THOMAS PRAYS IN AN ALL-NIGHT MASS VIGIL.

THE CROWD IS WAITING FOR THE PRIEST'S SIGN THAT THIS WATER FROM THE NILE IS BLESSED.

ALAMU: WHEN THE CROSS TOUCH THE WATER, IT MEANS THE BAPTISM IS JUST BEGIN AND EVERYBODY WILL JUMP UP AND JUST BAPTIZE.

IT'S THE BIGGEST CELEBRATION OF THE YEAR.

BIGGER THAN CHRISTMAS.

NARRATOR: WORSHIPPERS BELIEVE THAT THE NILE'S WATERS HAVE EXTRAORDINARY POWERS OF REBIRTH AND TRANSFORMATION.

THEY FEEL LIKE THEY ARE BAPTIZED AND THAT'S TRUE.

WHEN THEY GET THE HOLY WATER, THEY FEEL LIKE THEIR SINS GO AWAY.

NARRATOR: THOMAS TAKES HIS TIME... SAVORING THE MOMENT IN PRAYER.

WHEN AFTER I'M JUMPING INTO THE WATER AND JUST COMING OUT, WOW!

IT PUTS A SMILE ON MY FACE.

I FEEL LIKE AMAZING.

I DON'T KNOW HOW I'M GOING TO EXPLAIN BUT I FEEL LIKE I AM PEACEFUL MAN.

NARRATOR: AS THE BLUE NILE LEAVES ITS SACRED BEGINNINGS, IT TRANSPORTS ITS RICH WATERS ACROSS THE HEART OF ETHIOPIA...

BREATHING LIFE INTO EVERYTHING IT TOUCHES.

VARIED AND EXOTIC WILDLIFE MAKE THE MOST OUT OF THESE WATERS.

FROM AFRICA'S MOST ENDANGERED CARNIVORE, THE ETHIOPIAN WOLF... TO SOME OF THE CONTINENT'S MORE ADVENTUROUS CHARACTERS.

[MONKEYS CHATTERING] [BIRDS CHIRPING] MALE VILLAGE WEAVER BIRDS BUILD INTRICATE NESTS... AND DISPLAY THEIR SKILLS TO SCRUTINIZING FEMALES.

ONLY THE GREENEST NESTS ARE OF INTEREST.

FEMALES FLY FROM NEST TO NEST, GIVING EVERYTHING THE ONCE-OVER.

BROWN NESTS JUST DON'T CUT IT.

SO, THESE MALES WILL HAVE TO UNDO ALL OF THEIR HARD WORK AND START OVER...

WHILE OTHER MALES WILL USE EVERY TRICK IN THE BOOK TO AVOID A REBUILD... DISGUISING THE BROWN WITH FRESH STRANDS OF VEGETATION.

BUT THE FEMALES AREN'T SO EASILY TAKEN IN.

THEY'VE SEEN IT ALL BEFORE.

THIS YOUNG WEAVER IS TRYING TO BUILD ONE OF HIS FIRST NESTS.

IT TAKES YEARS TO PERFECT THIS INTRICATE AND DELICATE TASK, AND SO FAR, THIS NOVICE HAS ONLY SUCCEEDED IN TYING HIS FOOT TO THE PAPYRUS.

IT'S NOT IMPRESSING THE LADIES.

BUT HIS NEIGHBOR HAS PARTICULARLY EXPERT NEST-BUILDING SKILLS.

HE MAKES TRIPS TO THE WATER TO GET THE VERY BEST NESTING MATERIAL THAT THE BLUE NILE CAN PROVIDE.

AND HE HAS MASTERED THE ART OF TYING KNOTS WITH HIS BEAK AND FEET.

HE IS CLEARLY A SUCCESS WITH THE LADIES.

THIS ROMANTIC INTERLUDE IS THE PERFECT OPPORTUNITY FOR THE NOVICE TO STEAL SOME OF THE EXPERT'S NEST MATERIAL.

BUT HOWEVER HARD HE TRIES, HE JUST CAN'T SEEM TO GET IT RIGHT.

PERHAPS, WITH A BIT OF PRACTICE, THIS NOVICE WILL BE MORE SUCCESSFUL NEXT YEAR.

IT'S NOT JUST BIRDS THAT BUILD THEIR LIVES AROUND THE LUSH VEGETATION HERE.

PAPYRUS REEDS OF THE BLUE NILE HAVE ALSO BEEN IMPORTANT TO PEOPLE SINCE THE DAWN OF CIVILIZATION.

ESPECIALLY ON THE BLUE NILE'S BIGGEST RESERVOIR--LAKE TANA.

FOR MANY, BOATS MADE OUT OF PAPYRUS ARE THE ONLY MEANS OF TRANSPORTATION.

[VILLAGER SPEAKING NATIVE LANGUAGE] NARRATOR: PAPYRUS STALKS ARE BUOYANT, FLEXIBLE, AND EASY TO GATHER.

BUT BOATS STILL NEED REPLACING REGULARLY, SO, VILLAGERS NEED TO BE SKILLFUL AND QUICK IN THIS ART.

[VILLAGER SPEAKING NATIVE LANGUAGE] NARRATOR: THIS KNOWLEDGE HAS BEEN PASSED DOWN FOR HUNDREDS OF GENERATIONS.

[VILLAGER SPEAKING NATIVE LANGUAGE] NARRATOR: MAKING A WATERTIGHT BOAT IS AN ESSENTIAL RITE OF PASSAGE FOR THE CHILDREN OF THIS LAKE.

THIS EXPERTISE WILL SECURE THEIR FUTURE AND ALLOW THEM TO THRIVE ON THE LIFE-GIVING WATERS OF THE BLUE NILE.

THESE WATERS EVENTUALLY ENTER SUDAN, JOINING AND SUPPLEMENTING THE DWINDLING WHITE NILE.

HERE IN KHARTOUM, THEIR COMBINED POWER ALLOWS THEM TO TACKLE THE FINAL BUT MOST CHALLENGING LEG OF THE JOURNEY.

CROSSING THE SAHARA--THE LARGEST HOT DESERT IN THE WORLD.

AN EXPANSE OF SAND THE SIZE OF CHINA... WHERE TEMPERATURES TOP 120 DEGREES.

IN THIS DESERT WORLD, LIFE SEEMS LIKE AN IMPOSSIBILITY.

BUT THE NILE PERSISTS, A FRAGILE RIBBON OF BLUE IN AN OCEAN OF SAND...

ALLOWING LIFE TO APPEAR OUT OF THE DUST.

HERE IN SUDAN, AN EARLY CIVILIZATION THAT ONCE RIVALED ANCIENT EGYPT GREW ON THE NILE'S BANKS.

THIS GREAT CITY OF MEROE WAS THE STRONGHOLD OF THE KINGDOM OF KUSH, A GREAT NILE EMPIRE THAT ROSE 4,000 YEARS AGO...

THRIVING OFF TRADE MADE POSSIBLE BY THE RIVER.

BUT THIS ONCE-REMARKABLE KINGDOM HAS NOW BEEN RECLAIMED BY THE SAHARA AND ONLY ITS 200 PYRAMIDS REMAIN.

A REMINDER OF JUST HOW EPHEMERAL CIVILIZATIONS ARE IN THIS DESERT WORLD... AND THAT NOT EVEN THE LIFE-GIVING NILE CAN LIVE FOREVER.

THE NILE LEAVES SUDAN AND CONTINUES ITS VOYAGE THROUGH THE SAHARA TO BECOME THE ONLY PERMANENT RIVER IN EGYPT... [CAMEL BELLOWING] MAKING ITS WATERS MORE CRITICAL THAN EVER TO THOSE THAT LIVE HERE.

[CAMEL BELLOWING] ONE ANIMAL HAS AN INCREDIBLE ABILITY TO TAKE THE NILE'S WATER WITH IT WHEREVER IT GOES.

ABLE TO CONSUME 52 GALLONS OF WATER IN JUST 3 MINUTES, CAMELS CAN GO MONTHS WITHOUT DRINKING AGAIN... [CAMEL BELLOWING] ALLOWING THEM TO VENTURE DEEP INTO THE DESERT.

A MOVING OASIS.

FOR 3,000 YEARS, THEY HAVE PROVIDED DESERT PEOPLE WITH TRANSPORTATION, MILK, AND FOOD.

[MEN SINGING IN NATIVE LANGUAGE] THEY ALSO PROVIDE IN ANOTHER, MORE UNEXPECTED WAY.

WATER IS SO SPARSE OUT HERE THAT CREATURES WHO LIVE IN THIS DESERT WILL TAKE WATER WHEREVER AND IN WHATEVER FORM THEY CAN GET IT.

ENTER THE DUNG BEETLES.

BROUGHT IN FROM MILES AROUND BY THEIR INCREDIBLE SENSE OF SMELL.

AND ONCE THEY'VE FOUND IT, THE GAME IS ON TO SEIZE THE TREASURE AND HIDE IT AWAY.

IT'S A FEAT EQUIVALENT TO A HUMAN PUSHING A CAR UP A STEEP HILL.

BUT WORTH THE EXERTION.

BECAUSE THE MOISTURE CONTAINED IN CAMEL DUNG MAY BE THE ONLY WATER THIS BEETLE COMES ACROSS IN ITS ENTIRE LIFETIME.

THIS DESERT IS SO ARID THAT ONLY THOSE WITH EXTREME ADAPTATIONS CAN LIVE AWAY FROM THE NILE.

BUT THE HUMAN NEED FOR WATER IS SO CRITICAL THAT CIVILIZATION IN THE SAHARA IS FOREVER CHAINED TO THE RIVER.

AND REMARKABLY, LIFE NOT ONLY SURVIVES ON THE NILE...

IT THRIVES.

95% PERCENT OF EGYPT'S POPULATION LIVES ON THE NILE'S BANKS... MAKING CAIRO ONE OF THE MOST DENSELY POPULATED PLACES ON EARTH.

HOME TO 20 MILLION PEOPLE, THIS IS THE BIGGEST DESERT CITY IN THE WORLD.

FAMOUS FOR ITS VIBRANT, EXOTIC MARKETS... WITH AN ABUNDANCE OF CROPS GROWN FROM THE NILE.

BUT THERE'S AN INCREASING SILENT PRESSURE ON THIS CITY.

THE DEMANDS ON THE NILE'S WATERS ARE EXCEEDING ITS SUPPLY.

IT IS PREDICTED THAT BY 2025, CAIRO WILL BE RUNNING OUT OF WATER.

THE NILE'S FUTURE HANGS IN THE BALANCE.

AND IN THIS GREAT DESERT, THE NILE'S WATERS ARE EVERYTHING.

IT'S JUST AS TRUE NOW AS IT WAS 5,000 YEARS AGO...

WHEN THE NILE GAVE RISE TO ONE OF THE GREATEST KINGDOMS IN EARTH'S HISTORY.

ANCIENT EGYPT.

FOR 3,000 YEARS, IT WAS A PINNACLE OF CIVILIZATION.

THE NILE WAS SO IMPORTANT THAT PHARAOHS CLAIMED THEY HAD POWER OVER ITS WATERS.

THIS GAVE THEM THE OBEDIENCE OF THE EGYPTIAN PEOPLE... WHO KNEW THEY WERE UTTERLY DEPENDENT ON THE RIVER'S FLOW.

THEY CALLED THE NILE THE MOTHER OF ALL MEN... AND WORSHIPPED ITS MIRACULOUS ABILITY TO BRING LIFE TO WHERE THERE WOULD OTHERWISE BE NONE.

STILL TODAY, THE NILE'S INCREDIBLE JOURNEY IS CELEBRATED ALL ALONG ITS GREAT LENGTH.

FROM ITS MOUNTAINOUS BEGINNINGS TO ITS DESERT ENDING.

THOSE THAT LIVE IN THE REMARKABLE WORLDS OF THE NILE USE ITS WATERS IN VARIED AND ASTONISHING WAYS.

AND AFTER 4,000 MILES OF VOYAGING THROUGH AFRICA, THE NILE FINALLY COMPLETES ITS JOURNEY IN THE MEDITERRANEAN SEA, HAVING BROUGHT LIFE TO ALL SHE HAS TOUCHED.

ANNOUNCER: TO ORDER "RIVERS OF LIFE" ON DVD, VISIT shopPBS, OR CALL 1-800-PLAY-PBS.

THIS PROGRAM IS ALSO AVAILABLE ON AMAZON PRIME VIDEO.

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