>> Geller: MILLIONS OF PEOPLE VISIT THE EIFFEL TOWER, EXPLORE THE LOUVRE, AND ROAM THE LUXEMBOURG GARDENS EVERY YEAR. LITTLE DO THEY KNOW THAT BENEATH THEIR FEET LIES A WORLD OF SECRET HIDEOUTS AND ENDLESS LABYRINTHS. IT SNAKES AROUND. IT KEEPS GOING, HUH? FROM OFF-LIMITS UNDERGROUND NAZI BUNKERS-TURNED-GRAFFITI DENS... >> MORE OR LESS LIKE... >> Geller: OH, WOW! LOOK AT THIS! ...TO AN ANCIENT ROMAN CITY BURIED BENEATH THE NOTRE DAME... AND SO THERE'S, WHAT, 600 YEARS BETWEEN THESE 2 SITES THAT ARE 5 FEET APART? OH, GEE. ...AND EVEN AN UNDERGROUND CAVERN MADE ENTIRELY OF HUMAN BONES... GOD. THIS IS LIKE NOTHING THAT I'VE EVER SEEN BEFORE. ...PARIS'S UNDERGROUND IS A VAST SYSTEM OF TUNNELS... OH, MAN, YOU GOT PAGES AND PAGES. ...FILLED WITH DARK SECRETS AND HIDDEN PIECES OF THE PAST. THIS IS WHAT URBAN UNDERGROUND EXPLORING IS ALL ABOUT. I'M TEAMING UP WITH PARIS'S UNDERGROUND FANATICS... >> FIRST, WE HAVE TO CLIMB OVER THE WALL. CAN'T GO THROUGH. >> Geller: SO, I'M BREAKING INTO SOME JOINT RIGHT NOW. ...TO UNCOVER THE SUBTERRANEAN CITY LURKING BELOW THE CITY OF LIGHT. WE'RE PEELING BACK THE LAYERS OF TIME ON "CITIES OF THE UNDERWORLD: PARIS -- CATACOMBS OF DEATH." CAPTIONS PAID FOR BY
AUTHENTIC ENTERTAINMENT IT'S THE CAPITAL CITY OF FRANCE, AND WITH OVER 2 MILLION RESIDENTS, PARIS IS ONE OF THE LARGEST CITIES IN EUROPE. IT HAS MANY STORIES TO TELL AND AN UNDERGROUND FILLED WITH SECRETS. I'M ERIC GELLER. I'M IN PARIS, FRANCE, EUROPE'S CITY OF LIGHTS. HOME TO THE EIFFEL TOWER AND THE LOUVRE, IT IS<i> THE</i> MOST VISITED CITY IN THE WORLD. BUT THERE IS MORE TO PARIS THAN MEETS THE EYE. WHILE TOURISTS ARE ADMIRING THE VIEWS UP ABOVE, THERE IS ANOTHER WORLD LURKING DOWN BELOW. THERE ARE OVER 100 MILES OF LIMESTONE TUNNELS, HIDDEN BUNKERS, ANCIENT WATERWAYS, AND BONE-FILLED CRYPTS BURIED BENEATH THE STREETS. MOST OF THIS UNDERWORLD IS SEALED OFF TO THE PUBLIC, BUT THAT DOESN'T STOP PARISIANS FROM EXPLORING THIS PARALLEL WORLD. PARIS'S UNDERWORLD IS FILLED WITH THE LIVING AND THE DEAD, AND ITS SECRETS ARE ABOUT TO BE REVEALED. TODAY, PARIS IS HOME TO SOME OF THE MOST PROMINENT UNIVERSITIES, MUSEUMS, AND ARCHITECTURE IN THE WORLD, MAKING IT A HOT SPOT FOR MILLIONS OF VISITORS EVERY YEAR. BUT AS VISITORS TAKE IT ALL IN, MOST DON'T KNOW THAT THEY'RE ACTUALLY WALKING ON TOP OF A VAST SUBTERRANEAN CITY DATING BACK OVER 2,000 YEARS. THE TUNNELS WERE FIRST DUG BY THE ROMANS AFTER THEY CONQUERED GAUL, THE REGION THAT TODAY MAKES UP MODERN FRANCE. GAUL'S SOIL WAS RICH IN LIMESTONE, A FAVORITE BUILDING MATERIAL OF THE ROMANS, SO THEY QUARRIED THE TUNNELS BELOW TO CONSTRUCT THEIR CITY ABOVE. SINCE THEN, 2,000 YEARS OF CONSTANT DIGGING AND CORING HAS LEFT BEHIND OVER 180 MILES OF CATACOMBS UNDERNEATH PARIS. THE WORD "CATACOMB" OFFICIALLY MEANS AN UNDERGROUND BURIAL, BUT PARISIANS USE THE WORD MORE BROADLY TO REFER TO THE ENTIRE LABYRINTH THAT SNAKES DIRECTLY BENEATH THEIR HOMES, RESTAURANTS, AND STREETS. LESS THAN A HALF MILE OF THE 185 MILES IS OPEN TO THE PUBLIC. THE REST IS A DANGEROUS AND UNSTABLE WORLD. THERE'S EVEN A RUMOR THAT THE MANHOLES IN PARIS HAVE BEEN WELDED SHUT BY THE POLICE TO PREVENT PEOPLE FROM GOING DOWN, BUT THIS HASN'T STOPPED THE PARISIANS. THROUGHOUT HISTORY, THE TUNNELS HAVE BEEN USED AS CEMETERIES, HOLDING THE BONES OF UP TO 6 MILLION PEOPLE. DURING WORLD WAR II, THEY WERE OCCUPIED BY BOTH THE FRENCH RESISTANCE AND NAZI FORCES. OVER THE YEARS, THE STREETS HAVE COLLAPSED AND BEEN REINFORCED -- A MAJOR CHALLENGE FOR PARISIAN ARCHITECTS AND ENGINEERS. TODAY, THERE ARE RUMORS OF GANGS AND EVEN A SUBTERRANEAN POLICE FORCE PATROLLING THE CATACOMBS, AND THERE'S ONE GROUP WHO KNOWS THE SECRETS OF THE UNDERWORLD BETTER THAN ANYONE ELSE. THESE URBAN EXPLORERS CALL THEMSELVES "CATAPHILES," AND THE MORE THEY EXPLORE, THE MORE THEY DISCOVER. RECENTLY, THEY FOUND A LOST 200-YEAR-OLD BREWERY-TURNED-GRAFFITI-DEN BURIED MORE THAN 60 FEET BENEATH A MODERN APARTMENT BLOCK, AND I WAS GOING DOWN TO SEE IT ALL. CATAPHILE CLéMENT MENARD WOULD BE MY GUIDE ON THIS COVERT UNDERWORLD ADVENTURE. CLéMENT? >> YES. >> Geller: BONJOUR, CLéMENT. >> HOW ARE YOU? >> Geller: SO, YOU GOT AN UNDERWORLD TO SHOW ME -- SOME HIDDEN SECRET KIND OF...? >> YES, IT'S RIGHT DOWN HERE IN PARIS. YOU READY TO COME WITH ME TO DISCOVER IT? >> Geller: YEAH, LET'S GO. >> FIRST, WE HAVE TO CLIMB OVER THE WALL. CAN'T GO THROUGH. >> Geller: WE HAVE TO CLIMB? >> FOLLOW ME. DO AS I DO. >> Geller: SO, YOU UNDERSTAND THE UNDERWORLD I'M LOOKING FOR? >> YES. >> Geller: SO, I'M BREAKING INTO SOME JOINT RIGHT NOW. >> JUST WATCH THE STEP. >> Geller: ALL RIGHT. I FOLLOWED CLéMENT DOWN AN ABANDONED RAILWAY TRACK. THERE'S DEAD BODIES IN THERE. I GUARANTEE YOU, THERE'S DEAD BODIES IN THERE. FEW NON-CATAPHILES HAD EVER DONE WHAT I WAS ABOUT TO DO. WE GETTING CLOSE HERE? 'CAUSE THIS LOOKS LIKE ONE DARK TUNNEL HERE. IT LOOKS REALLY LONG. >> YEAH, IT'S PRETTY LONG. THE ENTRANCE IS ACTUALLY IN THERE. WE'RE GOING TO BE IN THE DARK, SO YOU NEED ONE OF THOSE. >> Geller: ALL RIGHT. >> WE CAN GO THROUGH THERE, AND THEN WE'LL FIND A HOLE IN THE WALL AND GO INTO THE CATACOMBS. SO, HERE WE ARE. THIS IS THE ENTRANCE. >> Geller:<i> THIS</i> IS THE ENTRANCE? THIS DOESN'T LOOK LIKE IT WAS DESIGNED TO HAVE PEOPLE GO THROUGH. IT LOOKS LIKE SOMEBODY BROKE THROUGH. >> YEAH, SOMEBODY BROKE THROUGH. I'LL GO DOWN FIRST, AND THEN YOU CAN COME. >> Geller: AS I DROPPED THROUGH THE MAN-MADE HOLE IN THE GROUND, I SAID GOODBYE TO THE SURFACE FOR THE NEXT EIGHT HOURS. >> THE CEILING IS PRETTY LOW, SO YOU HAVE TO WATCH OUT YOUR HEAD. >> Geller: ALL RIGHT. [ Chuckling ] OH, YEAH, THIS IS A MAN-MADE CAVE. I MEAN, THIS FEELS LIKE WE'RE SNEAKING OUT OF A PRISON -- YOU KNOW, WORLD WAR II. >> [ Chuckling ] YEAH. NOW YOU FOLLOW ME. >> Geller: OKAY. [ GRUNTS ] WE CRAWLED THROUGH THE WINDING TUNNELS AND GOT A TASTE OF WHAT IT WAS LIKE TO WORK IN THESE CRAMPED SPACES. >> I CALL "HEAD" WHEN YOU HAVE TO WATCH YOUR HEAD BECAUSE THE CEILING IS LOW, OR I CALL "FEET" WHEN THERE'S ANYTHING LIKE A BIG ROCK OR A HOLE. OTHERWISE, YOU'RE GOING TO BREAK AN ANKLE OR HIT YOUR HEAD, AND THERE'S NO ACCESS TO NO ONE. SO, HERE, FEET. >> Geller: FEET. >> AND NOW WATCH YOUR HEAD. >> Geller: WATCH MY HEAD. >> WATCH YOUR FEET. >> Geller: [ Grunting ] YEAH. HANDS AND KNEES, BABY. HANDS AND KNEES. FOR THOUSANDS OF YEARS, AN INCREDIBLE AMOUNT OF LIMESTONE WAS QUARRIED IN THESE CLAUSTROPHOBIC SPACES TO BUILD THE CITY ABOVE. >> WE'RE GOING TO GO LEFT HERE. >> Geller: THE TUNNELS WERE NOT ONLY DIFFICULT TO CLIMB THROUGH, THEY WERE ALSO DISORIENTING. CLéMENT HAD AN ENORMOUS BOOK OF MAPS. OH, MAN, YOU GOT PAGES AND PAGES. >> EXACTLY. [ CHUCKLES ] >> Geller: BUT THAT WAS NO GUARANTEE WE'D BE SAFE. EVEN THE MOST AVID OF CATAPHILES KNOWS IT'S A RISK TO ENTER THE VAST UNDERWORLD. IF LIGHTS GO OUT OR YOU LOSE YOUR WAY, YOU MIGHT NEVER MAKE IT BACK UP. IN FACT, IN 1793, A MAN DISAPPEARED INTO THE CATACOMBS. 11 YEARS LATER, IT WAS SAID THAT HIS CORPSE WAS FOUND CLUTCHING A SET OF KEYS, JUST A FEW FEET AWAY FROM AN EXIT, INVISIBLE TO HIM IN THE DARK. NOW, WHAT HAPPENS IF WE LOSE OUR POWER AND WE'RE STUCK IN THE MIDDLE OF THIS MAP? CAN YOU GET ME OUT OF HERE? >> WE COULD TRY, BUT WITHOUT POWER, IT'S DIFFICULT. >> Geller: [ SIGHS ] SEE, THIS IS WHAT URBAN UNDERGROUND EXPLORING IS ALL ABOUT. CLéMENT WAS TAKING ME TO A PLACE SO SECRET, EVEN MOST OF THE OTHER CATAPHILES DON'T KNOW ABOUT IT -- THE LOST BREWERY. SEE YOU ON THE OTHER SIDE. BUT IT WASN'T EASY TO GET TO. FACEFIRST, HUH? >> YEAH. >> Geller: OH, MAN, HOW DO I GET MY AMERICAN FAT ASS THROUGH THERE? [ GRUNTS ] ALL RIGHT. I HAD ALREADY CRAWLED ON MY HANDS AND KNEES, SQUEEZED THROUGH TINY HOLES. OF ALL THE TIMES NOT TO WEAR WATERPROOF BOOTS. AND NOW I WAS WADING KNEE-DEEP IN GROUNDWATER FROM THE EARTH BELOW. OH, YEAH, I'M SWIMMING IN IT RIGHT NOW. >> [ CHUCKLES ] >> Geller: IS IT ALWAYS LIKE THIS, OR JUST BECAUSE IT'S THE RAINY SEASON NOW? >> NO, IT'S MOSTLY ALWAYS LIKE THIS. IT'S NOT THAT HIGH, ACTUALLY. COUPLE YEARS AGO, IT WAS, LIKE, UP TO HIPS. >> Geller: AFTER ANOTHER 20 MINUTES OF SLOSHING, WE FINALLY HIT DRY LAND. >> NOW IT'S GETTING DRIER. >> Geller: OH, DRIER NOW. ONLY UP TO MY ANKLES IN WATER. I WAS ALMOST 45 FEET DOWN IN QUARRIES FIRST MINED NEARLY 2,000 YEARS AGO BY THE ROMANS. TODAY, THE CATACOMBS ARE FILLED WITH BIZARRE SYMBOLS OF MODERN GRAFFITI -- EVIDENCE OF THE URBAN EXPLORERS THAT CAME BEFORE ME. AND WE'RE NOT EVEN HALFWAY THERE YET, ARE WE? >> NO, NO. >> Geller: FEET. GOT SOME ROCKS HERE. >> WE'RE CLOSE TO THE PLACE I WANTED TO SHOW YOU FIRST -- VERY CLOSE ON THE LEFT. IT'S JUST A FEW -- 50 -- YARDS. >> Geller: HE SAYS, "50 YARDS," AND HE MEANS "ANOTHER HALF A MILE." THE HELL WITH IT. LET'S GO. LET'S KEEP GOING. WE WERE ABOUT TO HIT THE BREWERY, BUT FIRST, WE HAD TO WIGGLE THROUGH A 2-FOOT CRAWL SPACE FOR 30 FEET. AW, MAN, IT'S JUST LIKE WE'RE THE MILITARY, BABY. WE LANDED ON NORMANDY BEACH. WE'RE GOING TO HIT OUR POSITION. >> YES. OKAY, NOW JUST FOLLOW ME. SQUEEZE SOME SPACE TO CRAWL IN IT. >> Geller: [ Sighing ] OH, BOY. HERE WE GO, BABY. I'LL SEE YOU ON THE OTHER SIDE. [ GRUNTS ] THAT WASN'T TOO BAD. WE'RE JUST HAVING FUN NOW, BABY. ALL RIGHT, WHERE THE HELL ARE WE? WHAT AM I LOOKING AT? >> OH, THE BREWERY WAS UPSTAIRS, AND THIS IS, LIKE, THE BASEMENT OF THE BREWERY, WHERE THEY'RE STORING KEGS AND WINE AND WHATEVER. >> Geller: THIS IS THE BASEMENT OF A BREWERY? >> YEAH, THIS IS A BIG PLACE. >> Geller: THIS PLACE WAS THE GAULIA BREWERY. WE WERE IN ITS CELLARS, AND OVER 70 FEET ABOVE US WOULD HAVE BEEN THE STREET-LEVEL BUILDING. TODAY, IT'S GONE, AND AN APARTMENT BLOCK SITS ON TOP INSTEAD. THE SPACE SPANNED OVER 21,000 SQUARE FEET AND STOOD AROUND 8 FEET HIGH -- A MIDSIZE BREWERY FOR THAT TIME. IN THE LATE 19th CENTURY, THIS ANCIENT LIMESTONE QUARRY WOULD HAVE BEEN FULL OF BEER -- A CREATIVE USE FOR THE MILES OF GAPING HOLES HIDDEN BENEATH THE CITY. NOT ONLY WAS IT COST-EFFECTIVE, SINCE SPACE WAS SELLING AT A PREMIUM UP TOP, BUT THE COOL TEMPERATURES WERE PERFECT FOR STORING AND MAKING BEER. AND IN A COUNTRY FAMOUS FOR ITS WINE, SOME SAY IT WAS ACTUALLY THE FRENCH WHO TAUGHT THE GERMANS HOW TO MAKE BEER IN THE 8th CENTURY. BUT TODAY, INSTEAD OF BEER KEGS... >> MORE OR LESS LIKE... >> Geller: OH, WOW! LOOK AT THIS! ...WE FOUND AN EMPTY ROOM LINED WITH GRAFFITI, PAINTINGS, AND INCREDIBLE ARTWORK. THE BREWERY HAS BEEN TRANSFORMED INTO AN UNDERWORLD WORKSPACE FOR THE FEW ARTISTS THAT KNOW ABOUT THIS SECRET PLACE. CLéMENT, THIS IS -- THIS IS LIKE AN UNDERGROUND ART GALLERY HERE! >> EXACTLY. >> Geller: THIS IS FANTASTIC! IN THE TRADITION OF FINE PARISIAN ART. LOOK AT THIS. SOMEBODY WAS SPENDING SOME SERIOUS TIME DOWN HERE. >> PEOPLE CAME WITH MATERIAL TO PAINT AND EQUIPMENT AND SPENT HOURS DOING THIS. >> Geller: THIS WHOLE THING. >> YEAH. >> Geller: AND THEY HAVE NO IDEA WHAT GOES ON DOWN HERE. >> NOBODY. NO, NOBODY. >> Geller: THIS IS LIKE NOWHERE ELSE IN THE WORLD. THE BREWERY EVENTUALLY SHUT DOWN, AND, BY THE LATE 1970s, APARTMENTS ABOVE ERASED ANY SIGN OF THIS BEER-FILLED UNDERWORLD, MAKING IT PERFECT FOR CATAPHILES LIKE CLéMENT TO CREATE CLANDESTINE ART SPACES LIKE THIS ONE, ADDING THEIR OWN LAYER TO THEIR CITY'S UNDERWORLD. BUT THERE WAS MORE. [ GRUNTING ] CLéMENT WAS TAKING ME TO ANOTHER ROOM FEW HAVE EVER ENTERED. THIS ROOM HAD A DARKER STORY. THIS IS A SERIOUS IRON DOOR. >> THAT'S THE EXIT OF A BOMB SHELTER USED BY THE NAZIS IN THE SECOND WORLD WAR. >> Geller: DURING THE GERMAN OCCUPATION OF FRANCE, THE NAZI ARMY USED THESE TUNNELS AS A MAKESHIFT BOMB SHELTER. 60 FEET ABOVE OUR HEADS SITS A HIGH SCHOOL, WHERE THE NAZI AIR FORCE HAD ITS HEADQUARTERS. THE LUFTWAFFE -- THEY WERE RIGHT ABOVE US? >> RIGHT ABOVE US. >> Geller: AND THEY WERE USING THIS AS A BOMB SHELTER? BY UTILIZING THE MILES OF TUNNELS, THE NAZIS NOT ONLY HAD A READY-MADE BOMB SHELTER BUT WERE ALSO ABLE TO OPERATE IN SECRET. THEY ADDED SEALABLE IRON HATCH DOORS... HERE YOU WOULD HAVE PULLED THIS IN, AND YOU WOULD HAVE SEALED THE HATCH. YOU'VE GOT A REINFORCED BRICK WALL WITH SOME IRONWORKS AROUND IT. ...BENCHES TO WAIT ON DURING BOMB RAIDS... THESE WOULD HAVE BEEN BENCHES! >> BENCHES. >> Geller: THEY WOULD HAVE BEEN JUST LIKE THIS. THERE, YOU CAN SEE, THERE'S ONE OF THE BARS, AND THERE WOULD HAVE BEEN A SLAB OF WOOD. WE'D BE SITTING HERE AND WAITING FOR THE BOMBS. ...AND ELECTRICITY TO KEEP WORKING UNDERGROUND. >> THE POWER BOX. >> Geller: THIS WAS A POWER BASE HERE. HERE WE HAVE SOME OF THE CABLE. IT'S STILL INTACT. THEY EVEN ADDED UNDERGROUND LATRINES. YOU KNOW, COULD BE SOME NAZI TURDS STILL FLOATING AROUND HERE. I MEAN, THIS IS SOME EMBLEM OF NAZI OCCUPATION. AND IT STILL SMELLS LIKE IT IN THERE, TOO. >> [ CHUCKLES ] >> Geller: WHAT THE GERMAN OFFICERS DIDN'T KNOW WAS THAT ELSEWHERE IN THESE TUNNELS, LESS THAN A MILE AWAY, WAS THE UNDERGROUND HEADQUARTERS OF THE FRENCH RESISTANCE. >> EVERYBODY'S UNDERGROUND SO CLOSELY TO EACH OTHER BUT NOT KNOWING THEY'RE SO CLOSE. >> Geller: DURING WORLD WAR II, PARIS'S MAJOR PLAYERS ESTABLISHED A FOOTHOLD IN THE CITY'S UNDERGROUND. ENEMY FORCES UNKNOWINGLY SHARED THE SAME UNDERWORLD, SEPARATED BY JUST A FEW FEET OF LIMESTONE. BECAUSE PARIS WAS NOT HEAVILY BOMBED, THE SHELTER'S STRENGTH WAS NEVER PUT TO THE TEST, AND THE HEADQUARTERS OF BOTH THE NAZIS AND THE RESISTANCE REMAINED A SECRET. AS THEY STROLL ALONG THE BROAD STREETS AND PUBLIC SQUARES, MOST PARISIANS HAVE NO IDEA THAT THEY'RE WALKING ABOVE A BREWERY, AN UNDERGROUND GRAFFITI ART GALLERY, AND A SECRET BUNKER, AND ONLY A SELECT FEW WILL EVER EXPERIENCE THIS NETWORK OF WINDING UNDERGROUND CORRIDORS. >> THIS UNDERGROUND CULTURE THAT DEVELOPED RECENTLY, IN THE LAST 20, 30 YEARS -- THIS PAINTING, THIS CULTURE, VERY, VERY FEW PEOPLE KNOW ABOUT THAT. >> Geller: THE MASSIVE NETWORK OF TUNNELS CUT THROUGH 1,800 YEARS, DATING BACK TO THE ROMANS. AS THE CITY ABOVE GREW, SO DID ITS SUBTERRANEAN CITY. I'VE BEEN EXPLORING UNDERGROUND FOR HOURS, BUT I HAD ONLY SCRATCHED THE SURFACE OF PARIS'S UNDERWORLD. >> Geller: IT'S NO SECRET THAT MODERN PARIS IS ONE OF THE MOST BEAUTIFUL CITIES IN THE WORLD, BUT YOU DON'T HAVE TO GO FAR TO DISCOVER ITS DARK PAST. RIGHT BENEATH MY FEET, THERE ARE MASS GRAVES CONTAINING THE BONES OF OVER 5 MILLION PEOPLE. IT'S A LITERAL SUBTERRANEAN CITY OF THE DEAD. AS TOURISTS WALK PAST THIS ORDINARY OFFICE BUILDING, FEW KNOW THAT THEY'RE WALKING OVER ONE OF THE LARGEST BONEYARDS IN THE WORLD. ANDREW? >> YES. >> Geller: NICE TO MEET YOU. >> NICE TO MEET YOU, TOO. >> Geller: THANKS FOR MEETING WITH ME. AUTHOR ANDREW AYERS AND I HAD SPECIAL ACCESS TO GO DOWN INTO THE CATACOMBS ALONE. THE TUNNELS WE WERE WALKING THROUGH WERE JUST A SMALL PIECE OF THE 185 MILES LEFT BEHIND FROM THE LIMESTONE MINING THROUGHOUT THE YEARS. EVERY STEP TOOK US CLOSER TO A WORLD ACTUALLY MADE OF BONES. >> SO, HERE WE COME TO THE ENTRANCE TO THE CATACOMBS. WE HAVE THIS INSCRIPTION ABOVE THE DOOR, AS YOU CAN SEE, WHICH TELLS YOU EVERYTHING YOU NEED TO KNOW, REALLY. "STOP, THIS IS THE EMPIRE OF DEATH." SHALL WE, UH, GO IN? >> Geller: IT SAYS, "STOP," BUT I GUESS WE'RE GOING IN. >> I GUESS WE ARE. COME ON. >> Geller: UH-OH, ALL RIGHT. SO, THIS IS THE EMPIRE OF DEATH. WE'VE CROSSED THE THRESHOLD. >> WE'VE CROSSED THE LINE. >> Geller: NO<i> FRESH</i> CORPSES DOWN HERE, RIGHT? >> NO, I HOPE NOT. 20 METERS UNDERGROUND, SO... AND HERE WE HAVE... RATHER A LOT OF BONES LINED UP ALONG THE WALL. >> Geller: MY GOD. THIS IS, UH -- THIS IS -- THIS IS LIKE NOTHING THAT I'VE EVER SEEN BEFORE. >> WELL, BASICALLY, WHAT THEY DID WAS, AS YOU CAN SEE, THEY BUILT A RETAINING WALL. >> Geller: A RETAINING WALL OF BONES? >> OF FEMURS AND TIBIAS. >> Geller: MY GOODNESS. >> THAT'S WHAT THESE ARE. >> Geller: WHOA. BEHIND THE DECORATIVE RETAINING WALL LIES AN EVEN MORE SHOCKING SIGHT. >> THE BONE PATTERN'S JUST THE RETAINING WALL. BEHIND, YOU JUST HAVE A PILE OF BONES JUST THROWN IN A HEAP. >> Geller: THIS IS THE PRETTY BIT HERE? >> IT CAN GO BACK AS FAR AS 30 METERS NOW. >> Geller: SO IT COULD BE 100 FEET OF BONES JUST STACKED UP? >> OH, YES, HUGE, HUGE PILES. >> Geller: I'M LOOKING AT THIS WHOLE THING. IT'S SNAKING AROUND AND GOING ON AND ON. HOW LONG DOES THIS CORRIDOR OF BONES GO? >> DOWN HERE, THERE ARE 800 METERS OF CORRIDORS LINED WITH BONES. >> Geller: EXPERTS BELIEVE THERE ARE BETWEEN 5 MILLION AND 6 MILLION BODIES THAT MAKE UP THESE NEARLY 100-FOOT-LONG CORRIDORS OF THE DEAD. >> THEY THINK THERE ARE 6 MILLION SKELETONS. >> Geller: 6 MILLION SKELETONS? >> I DON'T KNOW HOW MANY BONES THERE ARE IN THE HUMAN BODY -- YOU DO THE CALCULATION -- BUT IT'S A LOT OF BONES. TO PUT IT INTO PERSPECTIVE, THE POPULATION OF PARIS TODAY IS SLIGHTLY OVER 2 MILLION. >> Geller: THERE'S MORE DOWN HERE THAN THERE ARE UP THERE. >> OH, YES, SO YOU HAVE 3 TIMES, BASICALLY. >> Geller: IT WAS INCREDIBLE. FOR EVERY PERSON WALKING UP ON THE STREETS, THREE SKELETONS WERE BURIED BELOW. SO, HOW DID THE REMAINS OF THREE TIMES THE POPULATION OF MODERN PARIS EVER WIND UP PILED HIGH IN AN ABANDONED LIMESTONE QUARRY, 65 FEET BENEATH THE GROUND? >> BASICALLY, THERE WERE THESE QUARRY VOIDS THAT WERE COLLAPSING THAT THEY HAD TO INSPECT AND SHORE UP AND CONSOLIDATE. AT THE SAME TIME, YOU HAD A PROBLEM WITH THE CEMETERIES IN CENTRAL PARIS. >> Geller: THE RISE OF CHRISTIANITY IN MEDIEVAL PARIS BROUGHT AN END TO THE PAGAN PRACTICE OF CREMATION, SO CEMETERIES AND CHARNEL HOUSES WERE NECESSARY TO STORE THE BODIES. RICH AND POOR ALIKE, EVERYONE WAS BURIED IN THE SAME MASS GRAVES. BUT AFTER SEVEN CENTURIES OF BURIALS, THERE WAS JUST NO MORE ROOM. >> BECAUSE THE CITY WAS SURROUNDED BY WALLS, IT COULDN'T EXPAND, SO YOU HAD CORPSES THAT WERE BASICALLY BURIED IN COMMUNAL PITS. THEY WERE LEFT TO ROT FOR A FEW YEARS. ONCE THE SPACE WAS FULL, THEY DUG THEM UP, PUT THE BONES IN CHARNEL HOUSES AROUND THE OUTSIDE OF THE CEMETERY, AND REUSED THE GROUND AGAIN. >> Geller: BY THE 18th CENTURY, THESE CEMETERIES WERE MAJOR HEALTH HAZARDS. IN THE CITY'S LARGEST CEMETERY, THE CIMETIèRE DES INNOCENTS, DECOMPOSING BODIES EVEN SPILLED INTO THE BASEMENT OF A NEARBY APARTMENT BUILDING. >> FOR ABOUT A CENTURY, PEOPLE WERE COMPLAINING ABOUT THE HORRIBLE MESS, AND THERE WERE EFFORTS TO TRY AND GET IT CLOSED, AND, FINALLY, AFTER YEARS AND YEARS AND YEARS, THEY DECIDED THAT, "REALLY, IT CAN'T GO ON," SO THEY CLOSED THE CEMETERY. THEN THEY HAVE TO THINK, "WELL, WHAT DO WE DO WITH THIS?" >> Geller: AT THE SAME TIME PARISIANS WERE STRUGGLING WITH WHERE TO PUT THE CORPSES, THE EMPTY QUARRIES WERE BEING CLEARED OUT AND REINFORCED. >> SOMEONE THOUGHT, "HANG ON A MINUTE. THERE'S ALL THESE TUNNELS THAT HAVE JUST BEEN CONSTRUCTED. WE HAVE ALL THESE CORPSES THAT WE NEED TO DO SOMETHING WITH. WHY DON'T WE PUT THEM DOWN IN THE QUARRY TUNNELS?" >> Geller: IT TOOK MONTHS TO TRANSFER ALL THE BODIES FROM THE CIMETIèRE DES INNOCENTS ALONE, BECAUSE THE BODIES HAD JUST BEEN PILED IN TO BEGIN WITH. THE NAMES AND STORIES OF THE DEAD WERE LONG FORGOTTEN. OVER THE NEXT 80 YEARS, PARIS'S POPULATION EXPLODED, AND THE CITY'S CEMETERIES COULDN'T KEEP UP. THE BODIES WERE MOVED RIGHT HERE TO THE SUBTERRANEAN EMPIRE OF THE DEAD. THEY WERE JUST CLEARING OUT GRAVEYARDS? >> EXACTLY, EXACTLY. THEY BROUGHT THEM BY NIGHT, IN CARTS, TIPPED THEM DOWN A HOLE FURTHER UP THERE, AND THEN ARRANGED THEM IN THESE PILES, AS YOU CAN SEE. >> Geller: I MEAN, LOOK AT THIS. THIS IS LIKE THE -- THIS IS THE BONEYARD. IT'S JUST HEAPS OF DIFFERENT BONES -- LITTLE PIECES OF FEMURS AND SKULLS, AND IT'S JUST ALL CHUCKED UP THERE. >> EXACTLY. >> Geller: MAN, IT'S JUST -- IT IS SURREAL. NOW, SOMEBODY CLEARLY WENT THROUGH A LOT OF TROUBLE TO MAKE THESE DESIGNS. LOOK AT IT. THIS IS A CROSS HERE. IT'S A CROSS MADE OF SKULLS. >> EXACTLY. >> Geller: THAT'S A LITTLE FREAKY. THESE WALLS OF SKULLS AND INTRICATE DESIGNS LOOK AS THOUGH THEY'VE BEEN RIGHT HERE FOR CENTURIES, BUT, BELIEVE IT OR NOT, THESE BONES ARE CONSTANTLY REARRANGED FOR STABILITY, AND THE DESIGNS ARE THE RESULT OF SOME CREATIVE THINKING. >> ONE THING YOU SHOULD BEAR IN MIND IS, OBVIOUSLY, BECAUSE THERE'S NOTHING HOLDING THESE TOGETHER, IS THAT, IF YOU LEFT THESE TO THEIR OWN DEVICES, THEY'D ALL FALL DOWN. SO THEY'RE ACTUALLY QUITE REGULARLY REBUILT. THEY RESTACK THE BONES INTO THESE PILES, SO IT'S AN ONGOING PROCESS STILL. >> Geller: WHEN THE FIRST ROMANS DUG THESE QUARRIES OVER 1,900 YEARS AGO, THEY NEVER COULD HAVE IMAGINED THAT, ONE DAY, THEY'D BE FILLED WITH BONES, USED AS BUNKERS, OR WOULD BECOME A PLAYGROUND FOR THE MOST DARING OF URBAN EXPLORERS. >> Geller: LONG BEFORE THE CITY OF PARIS WAS CREATED, RELIGION PLAYED A CRUCIAL ROLE IN ESTABLISHING AN UNDERGROUND WORLD. PARISIANS BUILT MASSIVE CATHEDRALS USING LIMESTONE QUARRIES FROM BENEATH THE GROUND, LEAVING MILES OF WINDING TUNNELS AS IMPRESSIVE AS THE STRUCTURES ABOVE. OPEN-AIR QUARRIES WERE FIRST DUG BY THE ROMANS IN THE 2nd CENTURY, BUT BY THE MEDIEVAL PERIOD, WORKERS HAD TO GO MUCH DEEPER IN THE GROUND TO EXTRACT ENOUGH STONE FOR STRUCTURES LIKE NOTRE DAME. AS MORE LIMESTONE WAS REMOVED FOR BUILDING ABOVEGROUND, THE TANGLE OF TUNNELS BELOWGROUND GOT BIGGER AND BIGGER. 500 YEARS LATER, THE QUARRIES HAD BEEN ABANDONED AND NOW POSED A MAJOR THREAT AS THE GROWING CITY BEGAN TO CAVE IN ON THE EMPTY CAVERNS. WORKERS WERE SENT DOWN TO FILL THEM IN AND REINFORCE THE NETWORK OF TUNNELS THAT RAN UNDER THE CITY. IT WAS DANGEROUS WORK AND INJURIES WERE COMMON, AND THE CLOSEST HOSPITAL WASN'T CLOSE ENOUGH. SO, IN THE LATE 1700s, A GROUP OF CAPUCHIN MONKS FOUNDED A HOSPITAL TO TREAT THE MEN WHO WORKED JUST BENEATH THEIR MONASTERY. [ HORNS HONKING ] A MODERN HOSPITAL STILL EXISTS ON THAT SITE TODAY, AND I'M ABOUT TO GET AN EXCLUSIVE LOOK AT THE DANGEROUS, SEALED-OFF UNDERWORLD BENEATH IT. YOU MUST BE GILLES. >> YEAH, AND YOU ARE ERIC? >> Geller: YES. BONJOUR, GILLES. >> BONJOUR, ERIC. I'M VERY PLEASED TO SEE YOU. >> Geller: UNDERGROUND EXPERT GILLES THOMAS GAVE ME SPECIAL ACCESS DOWN. >> FOLLOW ME TO SEE THE TRUE ROOTS OF PARIS. >> Geller: THE TRUE ROOTS? >> JUST THIS WAY. >> Geller: I WAS LEAVING BEHIND THE MODERN HOSPITAL AND HEADING BACK TO THE 13th CENTURY, INTO THE LABYRINTH OF LIMESTONE THAT LITERALLY BUILT PARIS. MY! 700 YEARS? THIS DEFINITELY LOOKS LIKE 700 YEARS OLD. THIS IS A PARALLEL UNIVERSE. THIS IS KIND OF SURREAL. IT LOOKS LIKE WE'RE IN ANCIENT EGYPT HERE. LOOK AT THESE LARGE LIMESTONE BLOCKS HERE, AND THERE'S A HOSPITAL 70 FEET ABOVE OUR HEAD? >> Geller: THIS QUARRY HAS BEEN AROUND FOR CENTURIES AND HAS PRODUCED BUILDING MATERIALS FOR STRUCTURES THROUGHOUT THE CITY. EXPERTS BELIEVE 30% OF THE LIMESTONE USED TO CONSTRUCT THE FAMOUS NOTRE DAME CATHEDRAL CAME FROM HERE. >> Geller: SO, THIS IS -- A QUARRYMAN IS WORKING DOWN HERE. OBVIOUSLY, HE DOESN'T HAVE A FLASHLIGHT, SO HE'S GOT A TORCH. AND HE'S HOLDING HIS TORCH HERE. AND IN THE OTHER HAND HE'S GOT A WEDGE? AND YOU CAN SEE SCRAPES ON THE CEILING. THIS IS WHERE YOU GET A SENSE OF WHAT WORK WAS LIKE DOWN HERE. IT WAS COLD, IT WAS DAMP, AND THEY'VE GOT A TORCH BURNING AND THEY'RE POUNDING AWAY DOWN HERE. I'LL SAY. BY THE MID-1700s, THE EXPANDING CITY BEGAN TO BEAR DOWN ON THE EMPTY CAVERNS BELOW. >> Geller: SOMETHING HAD TO BE DONE. A NEW ORGANIZATION WAS FORMED TO TAKE ON THE CHALLENGE OF REINFORCING THE NETWORK OF TUNNELS AND CAVERNS. >> Geller: WITH NEARLY 190 MILES OF TUNNELS AND CLOSE TO 2,000 YEARS OF CONSTANT CARVING AWAY AT PARIS'S LIMESTONE FOUNDATION, IT WAS A MASSIVE PROJECT. HUNDREDS OF WORKERS WERE SENT DOWN INTO THE DEEPLY UNSTABLE UNDERGROUND WORLD. MANY NEVER RETURNED. AND AS WE KEPT GOING DEEPER INTO THE QUARRIES, WE CAME ACROSS A CHILLING REMINDER OF JUST WHY THESE TUNNELS NEEDED EXTRA SUPPORT. THIS DOESN'T LOOK LIKE THE BEST REINFORCEMENT THAT I'VE EVER SEEN, SO I DON'T KNOW HOW THIS IS HOLDING UP. IN THIS CASE, THEY REINFORCED A TUNNEL UNDERNEATH THE POINT AT WHICH IT HAD COLLAPSED. THERE IS NO DOUBT THAT IF THERE WERE WORKERS DOWN HERE AT THE TIME OF THIS COLLAPSE, SOMEONE DIED IN THIS VERY SPOT. IT LOOKS VERY SAFE, BUT I'M GOING TO LET GILLES LEAD ON. GILLES, YOU GO FIRST AND LET ME SEE. >> OKAY, I GO FIRST. >> Geller: ALL RIGHT, WE'RE GOING TO MAKE IT. BUT IF NOT, I'M NOT GOING TO DISTURB ANYTHING. REINFORCING THE QUARRIES WAS NECESSARY TO SAVE THE CITY THEY HAD HELPED CREATE UP ABOVE. BUT FOR HUNDREDS OF WORKERS DOWN HERE, THE JOB BECAME A DEATH SENTENCE, AND MANY OTHERS ENDED UP IN THE HOSPITAL JUST ABOVE OUR HEADS. INJURY FROM THE TUNNELS COLLAPSING WASN'T THE ONLY THREAT DOWN IN THE LABYRINTH. THERE'S SO MANY DIFFERENT LITTLE NOOKS AND INTERESTING SPACES DOWN HERE. IT SNAKES AROUND. IT KEEPS GOING, HUH? IN THIS MAZE, ONE WRONG TURN COULD TRAP YOU DOWN HERE FOREVER. WE'RE WALKING AROUND, AND I CAN SEE IT'S LIKE A LABYRINTH OF DIFFERENT TUNNELS AND CORRIDORS THAT GO OFF IN DIFFERENT DIRECTIONS. WITHOUT THE BENEFIT OF MAPS, THOSE WHO REINFORCED THE QUARRY TUNNELS FOUND OTHER WAYS TO KEEP THEIR BEARINGS. NOW, I SEE THIS LINE HERE. WHAT IS THIS? IT LOOKS LIKE IT'S A TRAIL. IS THERE ANY REASON FOR THIS? >> THIS BLACK LINE WAS FOR HELPING PEOPLE WORKING FOR THE QUARRIES TO MOVE IN THE QUARRIES, NOT TO GET LOST. THIS LINE LEADS TO THE PLACE WHERE THEY WORK OR LEADS TO THE EXIT. >> Geller: TODAY, IT'S EASY TO FORGET THAT THERE'S A CITY OF MILLIONS OF PEOPLE UP ABOVE, BUT THERE ARE SOME REMINDERS. >> Geller: EVEN IN THE UNDERWORLD, WE HAVE AN ADDRESS. >> BECAUSE YOU NEED TO KNOW EXACTLY BELOW WHICH BUILDING YOU ARE. >> Geller: THE STREET SIGNS WERE PUT IN DURING THE TIME OF THE REINFORCEMENTS, AND THEY MIRROR EXACTLY THE LAYOUT OF THE STREETS OVER 60 FEET ABOVE OUR HEADS. >> AND HERE, AT THE RIGHT, TO HAVE A LITTLE TASTE OF THE SURFACE, JUST COME HERE AND SEE ABOVE YOUR HEAD. >> Geller: SO, IF WE GO UP -- THAT LOOKS ABOUT 75 FEET UP -- THAT'S THE SURFACE. SO I JUST GOT SPLASHED BY A DROPLET OF WATER FROM THE 21st CENTURY, AND IT FALLS ALL THE WAY DOWN TO THE 13th CENTURY. ABOVE US WAS JUST ONE OF MANY VERTICAL SHAFTS CONNECTING THE SURFACE TO THE QUARRY. THEY WERE BUILT IN THE 19th CENTURY TO PROVIDE EASIER ACCESS FOR THE INSPECTORS AND USED TO HAVE LADDERS AND PLATFORMS SNAKING DOWN THE WALL. THIS WAY, THE WORKERS COULD INSPECT AND REINFORCE THE TUNNELS WITHOUT TREKKING THROUGH THE ENDLESS MAZE. OVER THE CENTURIES, DOZENS OF REINFORCEMENT PILLARS HAVE BEEN ADDED. WITHOUT THESE PILLARS, THE PARIS WE KNOW WOULDN'T BE HERE TODAY, AND NEITHER WOULD THIS UNDERGROUND LABYRINTH. THIS IS SOLID LIMESTONE. LOOK AT THIS THING. THIS IS A HELL OF A PILLAR. BUT HOW DID THESE HUGE PILLARS GET TRANSPORTED DOWN HERE? THE ANSWER IS, THEY DIDN'T. INSTEAD, ENGINEERS DUG A WELL AND MIXED THEIR OWN CONCRETE 65 FEET BENEATH THE STREETS. THIS IS A WATER WELL. >> THIS IS THE EDGE OF THE WATER WELL. >> Geller: THE WATER FROM THE WELL WAS USED TO MAKE CONCRETE FOR THE REINFORCEMENT PILLARS. THEY WERE ACTUALLY USING THIS WATER TO MIX THEIR CONCRETE? THERE'S SO MANY HIDDEN JEWELS DOWN HERE. WHAT BEGAN AS A QUARRY TO HELP BUILD THE EXPANDING CITY ABOVE NEARLY LED TO THAT CITY'S LITERAL COLLAPSE. BUT WITH THE HELP OF SOME GUTSY WORKERS AND INGENIOUS THINKING, TODAY THE QUARRIES BENEATH THE HOSPITAL REMAIN INTACT AND HIDDEN FROM MODERN-DAY PARISIANS. >> JUST FOLLOW ME. >> Geller: UP NEXT, INSIDE PARIS'S WATER SYSTEM. THERE ARE ROOTS GROWING IN HERE, AND THEY'RE LITERALLY PUSHING APART THESE STONE SLABS. THIS DOES NOT MAKE ME FEEL VERY SECURE. AND LATER, AN ANCIENT ROMAN CITY BELOW NOTRE DAME. >> Geller: THE RIVER SEINE RUNS THROUGH THE HEART OF PARIS AND FOR 2,000 YEARS HAS PLAYED A MAJOR ROLE IN THE SUCCESS OF THE CITY. IT SUPPLIED ACCESS TO TRADE, MEANS OF TRANSPORTATION, AND DRINKING WATER, BUT IT ALSO HELPED TO CARRY CHOLERA AND THE PLAGUE, SO PARISIAN CITY PLANNERS CREATED AN UNDERGROUND WATER WORLD -- A WORLD THAT, EVEN TODAY, KEEPS THIS CITY UP ABOVE ALIVE. FOR HUNDREDS OF YEARS, PARISIANS HAD A CONSTANT SOURCE OF CLEAN WATER, THANKS TO THE SEINE. BUT BY THE MIDDLE AGES, THE CITY HAD GROWN SO BIG THAT IT BECAME IMPRACTICAL FOR PEOPLE TO CARRY WATER FROM THE RIVER TO THEIR HOMES. SO, IN THE 13th CENTURY, A SYSTEM OF UNDERGROUND AQUEDUCTS WAS CREATED TO BRING FRESH WATER TO FOUNTAINS ACROSS PARIS. I WAS ABOUT TO HEAD INTO THE WATERY DEPTHS, TO THE BEGINNINGS OF THE CITY'S URBAN INFRASTRUCTURE, TO FIND AN ENGINEERING MARVEL THAT ALLOWED THE CITY UP ABOVE TO FLOURISH. MONSIEUR de SERRE? >> YES. >> Geller: BONJOUR. THANK YOU FOR MEETING WITH ME. >> VERY NICE TO ASSIST YOU. >> Geller: UNDERGROUND EXPERT GERARD de SERRE WAS TAKING ME FROM THIS QUIET NEIGHBORHOOD, COMPLETE WITH A CHILDREN'S PLAYGROUND... >> OKAY, YOU READY? >> Geller: I'M READY. >> SO, LET'S OPEN, AND YOU FOLLOW ME. >> Geller: LET'S DO IT. ...BACK TO THE STARTING POINT OF THE FIRST AQUEDUCT OF MEDIEVAL PARIS. >> IT'S LIKE A TEMPLE DEDICATED TO WATER. >> Geller: A TEMPLE? >> YES. >> Geller: THAT'S WHAT IT LOOKS LIKE -- THE DOME FROM THE OUTSIDE. THIS TOWER, KNOWN AS THE REGARD de la LANTERNE, IS AT THE HEAD OF THE BELLEVILLE AQUEDUCT, WHICH, 700 YEARS AGO, WAS VITAL IF PARIS WAS GOING TO THRIVE AS A MAJOR CITY. IN THE 13th CENTURY, PARIS WAS FLOURISHING, NOTRE DAME WAS UNDER CONSTRUCTION, AND MORE THAN 200,000 PEOPLE LIVED HERE, SO THE AQUEDUCTS WERE NECESSARY FOR THE CITY TO SURVIVE. SO, THERE ARE THREE CHANNELS HERE THAT COLLECT WATER, AND IT DROPS IT ALL INTO HERE, INTO THIS BASIN. IT'S STILL WORKING. IT'S STILL COLLECTING WATER! IT'S INCREDIBLE. MEDIEVAL ENGINEERS DEVISED A WAY OF COLLECTING THIS PRECIOUS RESOURCE. GROUNDWATER WOULD NATURALLY FILTER THROUGH THE SOIL BEFORE HITTING AN EXISTING LAYER OF DENSE CLAY. SINCE IT COULDN'T PASS THROUGH THE CLAY, THE WATER WOULD SIMPLY ACCUMULATE IN THE TRENCHES AND SLOWLY TRICKLE DOWN INTO THE CENTRAL BASIN. DESPITE BEING MORE THAN 500 YEARS OLD, THIS SIMPLE TECHNOLOGY STILL WORKS TODAY, HIDDEN UNDER A PLAYGROUND. BUT THERE WAS MORE. WHAT DO YOU GOT THERE? LOOK AT THAT. >> JUST FOLLOW ME. >> Geller: OKAY. THAT'S AN OLD LANTERN, ISN'T IT? FROM THE MAIN ROOM, WE WERE ABLE TO FOLLOW THE WATER'S PATH BACK TOWARD ITS SOURCE. >> SO, THIS IS WHERE PEOPLE COULD GO FOR INSPECTION, AND WATER WAS JUST FLOWING IN THE SMALL TRENCH. >> Geller: MORE THAN 500 YEARS AGO, THIS IS WHERE INSPECTORS WOULD HAVE GONE TO MAKE SURE EVERYTHING WAS IN WORKING ORDER AND THAT THE WATER WAS CLEAN AND SAFE FOR DRINKING. WAS IT DESIGNED TO DO THAT? >> YES, IT WAS NECESSARY ALSO TO DRAIN THE WATER, NOT TO LET IT ACCUMULATE BEHIND THE WALLS. >> Geller: SO IT SERVED TWO PURPOSES -- NOT ONLY TO COLLECT WATER BUT ALSO TO DRAIN WATER. >> EXACTLY. >> Geller: THOUGH THE MEDIEVAL WALLS WERE STRONG ENOUGH TO LAST HUNDREDS OF YEARS, AS THE CITY RAPIDLY EXPANDED, THEY INEVITABLY BEGAN TO CRACK. >> THIS IS A REINFORCEMENT WHICH HAS BEEN MADE IN THE SECOND HALF OF THE 19th CENTURY TO AVOID COLLAPSING OF THE SLABS. >> Geller: BUT EVEN WITH THE MODERN REINFORCEMENTS, DOWN HERE IT'S A BATTLE BETWEEN CEMENT AND MOTHER NATURE. THERE ARE ROOTS GROWING IN HERE, AND THEY'RE LITERALLY PUSHING APART THESE STONE SLABS. THIS DOES NOT MAKE ME FEEL VERY SECURE. TODAY, THE BELLEVILLE AQUEDUCT MERELY SERVES AS A WAY OF DRAINING GROUNDWATER. SECTIONS OF IT HAVE BEEN SEALED OFF AND FILLED IN TO ALLOW NEW BUILDINGS TO BE CONSTRUCTED ABOVE IT. THESE TUNNELS ALLOWED THE CITY TO GROW FROM A MEDIEVAL TOWN INTO ONE OF THE GREATEST CITIES IN THE WORLD. BUT PROVIDING CLEAN DRINKING WATER WASN'T THE ONLY IMPORTANT JOB OF THE UNDERGROUND. GROWING CITIES MEAN MORE PEOPLE. MORE PEOPLE MEANS MORE WASTE. SO, ALONGSIDE THE AQUEDUCT AND SHARING THE SAME GROUND WITH THE MILES OF CATACOMBS IS A MASSIVE SEWAGE SYSTEM FAMOUS AROUND THE WORLD. I MET WITH PROFESSOR GEORGE WANKLIN... PROFESSOR WANKLIN? >> THAT'S ME. >> Geller: THANK YOU FOR MEETING WITH ME. >> MY PLEASURE. >> Geller: ...WHO'S GOING TO TAKE ME TO A PLACE THAT SAVED THE LIVES OF THOUSANDS OF PARISIANS. WE WERE IN JUST ONE SECTION OF THE 150-YEAR-OLD SEWAGE TUNNELS BENEATH THE STREETS, AND MODERN PARISIANS HAVE NO IDEA HOW LUCKY THEY ARE THAT THESE THINGS ARE DOWN HERE. COVERED SEWERS WERE FIRST BUILT IN PARIS IN THE 14th CENTURY. THEY STRETCHED JUST 15 MILES UNDERGROUND. THIS WASN'T NEARLY EXTENSIVE ENOUGH TO ACCOMMODATE THE NEW URBAN POPULATION. THE OVERFLOW OF SEWAGE WAS SO BAD THAT VISITORS SAID YOU COULD SMELL PARIS BEFORE YOU COULD SEE IT. >> WALKING AROUND IN PARIS, WHERE MANY OF THE STREETS WERE NOT PAVED AND WHERE ALL WASTE OF ALL SORTS WENT STRAIGHT OUT THE WINDOW AND INTO THE STREET, A GOOD PAIR OF BOOTS WOULD LAST YOU ONE YEAR IN PARIS BEFORE THEY'D BE EATEN AWAY BY WHAT WAS POLITELY CALLED THE MUD. >> Geller: THE ABYSMAL STATE OF SANITATION IN THE CITY LED TO A SERIES OF VIOLENT OUTBREAKS OF CHOLERA, A BACTERIAL DISEASE SPREAD BY WATER CONTAMINATED BY HUMAN WASTE. >> THE 1832 EPIDEMIC OF CHOLERA KILLED SOMEWHERE BETWEEN 18,000 AND 20,000 PARISIANS. AND THEN, ONLY 17 YEARS LATER, THERE WAS ANOTHER EPIDEMIC, WHICH KILLED 16,000 PEOPLE. >> Geller: FILTHY WATER WAS GOING TO TAKE DOWN THE CITY, SO PARIS EXPANDED THEIR SEWERS TO BECOME THE MOST MODERN AND EFFICIENT SEWERS IN THE WORLD AT THAT TIME. OVER 2 DECADES, THE PARIS SEWER SYSTEM GREW BY 450% TO 340 MILES. TODAY IT HAS GROWN TO OVER 1,000 MILES. >> IT'S NOW ABOUT 2,300 KILOMETERS. IF YOU LINED THEM ALL UP, THAT WOULD CARRY YOU FROM PARIS TO MOSCOW. >> Geller: BUT THE SEWERS MAKE UP ONLY A SMALL FRACTION OF WHAT LIES BENEATH THE CITY STREETS. >> YOU HAVE THE METRO SYSTEM, YOU'VE GOT CATACOMBS, YOU'VE GOT UNDERGROUND PARKING GARAGES. PARIS IS LIKE A SWISS CHEESE UNDERNEATH THE SURFACE OF THE CITY. >> Geller: WITHOUT THIS SATURATED SUBTERRANEAN, THIS CAPITAL CITY MIGHT NEVER HAVE BEEN. UP NEXT, NOTRE DAME'S UNDERGROUND SECRET. >> ABOVE OUR HEAD RIGHT NOW IS THE HUGE SQUARE IN FRONT OF NOTRE DAME CATHEDRAL. >> Geller: THERE'S PROBABLY 1,000 TOURISTS UP THERE, AND THEY DON'T KNOW WE'RE DOWN HERE. >> Geller: WHEN IT COMES TO GOTHIC ARCHITECTURE, NOTRE DAME CATHEDRAL IS ONE OF THE BEST EXAMPLES IN THE WORLD. FOR NEARLY 1,000 YEARS, PEOPLE HAVE FLOCKED HERE TO ADMIRE IT. BUT THE HISTORY OF THIS CHURCH GOES BACK MUCH FURTHER, AND BENEATH IT ARE REMNANTS OF A LOST ROMAN CITY. IN 52 B.C., JULIUS CAESAR CONQUERED ALL OF WHAT IS NOW FRANCE, AND, SOON AFTERWARD, A ROMAN TOWN CALLED LUTETIA, MEANING "MID-WATER DWELLING," AROSE ON THE BANKS OF THE SEINE. OVER THE NEXT TWO CENTURIES, THAT CITY WAS SLOWLY BURIED BY CONTINUAL BUILDING AND REBUILDING UNTIL IT WAS COMPLETELY LOST. A MASSIVE FACE-LIFT 150 YEARS AGO COMPLETELY RAZED THE OLD PARIS, MAKING WAY FOR ITS NOW-FAMOUS WIDE BOULEVARDS, BLOCK-LONG APARTMENT BUILDINGS, AND GRAND MONUMENTS. ROMAN AND MEDIEVAL PARIS WERE GONE, BUT NOT FOR LONG. 150 YEARS AFTER THE CITY GOT ITS FACE-LIFT, ENGINEERS WERE BREAKING GROUND UNDER THE SQUARE, AND THAT'S WHEN PARIS'S ROMAN UNDERWORLD CAME TO LIFE. MY JOURNEY TO FIND THE LOST CITY OF LUTETIA BEGINS AT ONE OF THE MOST IMPORTANT MONUMENTS IN THE WORLD -- NOTRE DAME. YOU MUST BE ELAINE. >> YOU MUST BE ERIC. >> Geller: NICE TO MEET YOU. THANK YOU FOR MEETING WITH ME. I MET WITH MEDIEVALIST ELAINE POLLEY, WHO AGREED TO TAKE ME BELOW NOTRE DAME, BACK TO PARIS'S ROMAN ROOTS. >> YOU ARE GOING TO FIND ANCIENT ROME, AND I'LL SHOW YOU HOW. >> Geller: GOING DOWN JUST 16 FEET BELOW STREET LEVEL, WE LEAPED BACK ALMOST 2,000 YEARS TO LUTETIA, A PROVINCIAL ROMAN TOWN OF 20,000 PEOPLE. IN THIS VERY SPOT, DOCKWORKERS AND FISHERMEN WOULD HAVE BEEN BUSY SUPPLYING GOODS TO THE SURROUNDING EMPIRE, USING ONE OF ROME'S MOST FAMOUS ENGINEERING MARVELS -- ROADS. AND WHAT ARE THESE? THESE LOOK GREAT, 'CAUSE I CAN IDENTIFY STEPS, I CAN SEE WALLS. >> WHAT YOU ARE LOOKING AT RIGHT HERE IS A 2nd- TO EARLY-3rd-CENTURY ROAD. >> Geller: LUTETIA'S THRIVING RIVERFRONT WAS THE EARLIEST KNOWN PORT IN FRANCE. ITS PRIME LOCATION ALONG THE BANKS OF THE SEINE ALLOWED THE CITY TO BOOM. >> THERE WAS A FORUM FOR DOING BUSINESS. OUTSIDE THE CITY, THERE WAS AN ARENA, WHICH WAS AN AMPHITHEATER FOR SHOWS. THERE MAY HAVE BEEN GLADIATORS. THERE WAS, WHERE NOTRE DAME CATHEDRAL STANDS NOW, A TEMPLE TO JUPITER. IT WAS A SMALL TOWN BUT A COMFORTABLE TOWN. >> Geller: THE SMALL TOWN, COMPLETE WITH ITS ARENA AND TEMPLES, SAT ON THE BANKS OF THE SEINE RIVER. OVER THE YEARS, BUILDUP AND GARBAGE HAVE CAUSED THE LOCATION OF THE RIVER TO MOVE 50 FEET. BUT IN ROMAN TIMES, WE WOULD HAVE BEEN WALKING DIRECTLY ON ITS BANKS. THIS WOULD HAVE BEEN THE BANKS OF THE RIVER, AND I'M LOOKING OUT AT THIS MONSTROSITY, AND IT GOES ON AND ON. >> YES, 2,000 YEARS AGO, YOU WOULD HAVE BEEN IN A FISHING BOAT, THROWING YOUR FISH UP ONTO THE EMBANKMENT. >> Geller: SO WE WOULD BE IN THE RIVER SEINE? >> WE WOULD BE. >> Geller: WHAT'S ABOVE OUR HEAD RIGHT NOW? >> ABOVE OUR HEAD RIGHT NOW IS THE HUGE SQUARE IN FRONT OF NOTRE DAME CATHEDRAL. >> Geller: THERE'S PROBABLY 1,000 TOURISTS UP THERE, AND THEY DON'T KNOW WE'RE DOWN HERE. AS ROMAN RULE BEGAN TO FALL IN THE 4th AND 5th CENTURIES, THE PEOPLE OF LUTETIA, NOW CALLED THE GALLO-ROMANS, HAD NO USE FOR ROMAN TEMPLES. INSTEAD, THEY NEEDED PROTECTION, SO THEY SIMPLY REUSED BLOCKS OF LIMESTONE, ORIGINALLY QUARRIED FROM THE CATACOMBS TO BUILD THEIR TEMPLES AND OTHER BUILDINGS, TO NOW BUILD THEIR MASSIVE AND MUCH-NEEDED FORTIFICATION WALL. ANCIENT RECYCLING AT ITS BEST. >> RIGHT HERE IN THE MIDDLE, YOU ARE LOOKING AT A SECTION OF GALLO-ROMAN WALL BUILT AT THE END OF THE 3rd CENTURY. >> Geller: BUT THIS 3rd-CENTURY WALL WAS MUCH OLDER THAN THAT. IT WAS ORIGINALLY PART OF AN ANCIENT ARENA THAT WAS ONCE PACKED WITH PEOPLE DURING THE HEIGHT OF ROMAN RULE. SO, THEY PILFERED THIS STONE FROM ANOTHER BUILDING -- FROM THE ARENA -- TO MAKE A NEW WALL HERE? >> THAT IS EXACTLY RIGHT. [ INDISTINCT SHOUTING ] THEY BUILT A WALL RIGHT HERE BECAUSE OF THE FIRST BARBARIAN INVASIONS, WHICH TOOK PLACE THE END OF THE 3rd CENTURY. ALL SORTS OF PEOPLE WERE INVADING IN THOSE DAYS -- THE GERMANIC TRIBES, LATER ON THE NORMANS. YOU ALSO HAD ATTILA THE HUN IN 451. >> Geller: IN THE 5th CENTURY, ONE TRIBE OF INVADERS, THE FRANKS, DID MAKE IT OVER THESE WALLS. THEY CLAIMED THE LAND AS THEIR OWN, AND, FROM THEN ON, IT WAS CALLED FRANCE IN THEIR NAME. THE FRANKS MADE PARIS THEIR CAPITAL CITY AND BUILT A CHURCH ON THIS SITE. >> OVER HERE TO THE RIGHT, YOU HAVE THE RUINS OF SAINT GENEVIEVE CHURCH. THEY BUILT A CHURCH SO THAT THEY COULD KEEP HER RELICS HERE, WHERE THEY WOULD BE SAFE INSIDE THE WALL. >> Geller: DATES TO WHAT ERA? >> DATES TO THE 9th CENTURY. >> Geller: AND SO THERE'S, WHAT, 600 YEARS BETWEEN THESE 2 SITES THAT ARE 5 FEET APART? >> THAT IS EXACTLY RIGHT. >> Geller: THIS SITE WAS USED YET AGAIN IN 1163, THIS TIME FOR ONE OF THE WORLD'S MOST IMPOSING STRUCTURES THAT TODAY JUST HAPPENED TO BE SITTING ABOVE OUR HEADS. >> SO MANY PEOPLE COME TO SEE NOTRE DAME BECAUSE, WHEN THEY THINK OF GOTHIC ARCHITECTURE, THEY THINK OF NOTRE DAME. >> Geller: AND THEY THINK OF THE EIFFEL TOWER OR THE LOUVRE OR THE WIDE BOULEVARDS THAT LEAD TO THE ARC de TRIOMPHE, BUT FEW THINK ABOUT WHAT LIES BENEATH. IT'S A WORLD OF REMNANTS FROM A LOST ROMAN CITY, BONE-FILLED CATACOMBS, INGENIOUS ENGINEERING THAT SAVED THE CITY FROM DISEASE, EVEN NAZI BUNKERS WHOSE WALLS HAVE BECOME A PALETTE FOR MODERN ARTISTS. BENEATH PARIS SITS A LIMESTONE LABYRINTH DATING BACK TO THE ROMAN EMPIRE, FULL OF ARTWORK, BUNKERS, SKULLS, AND BONES. TODAY, URBAN EXPLORERS ARE ADDING THEIR OWN LAYER. AND NEXT TIME YOU WALK OVER A MANHOLE IN THE STREETS OF PARIS, WHO KNOWS WHAT OR WHO IS BENEATH YOUR FEET?
