Original subtitles

Below the bustling streets of Seoul, South Korea,

an incredible discovery is made.

Beneath CitiStar Mall lies a vast chamber

just above the tracks of subway Line 2.

How does a space like this get constructed

in the middle of the city

then stay hidden from public view for so long?

What function was it meant to serve?

Excavations beneath a Polish ice cream shop

reveal a medieval gravesite.

The first discovery was a limestone slab

carved with the image of a man in full chainmail armor.

So who was he?

And what can his burial reveal about the forces

that shaped the city at its beginnings?

A remarkable discovery is made

under the rubble of a demolished church in England.

Three portrait busts made of stone.

This site was like an archaeological nesting doll,

each layer presenting a new mystery.

Who put all these items here

and what was this place?

Below the busy streets of the world's cities

exists a hidden realm of wonder.

Sprawling ancient complexes,

mysterious tombs,

top-secret military bases,

strange structures,

and lost artifacts,

buried beneath our feet and long forgotten...

until now.

Underground marvels are exposed to reveal what lies...

Hidden Beneath the Cities.

Less than 40 miles from the Yellow Sea,

the city of Seoul is located in South Korea,

which makes up the southern part of the Korean Peninsula.

The Korean Peninsula stretches

over 600 miles from north to south,

bordered by China and Russia,

with Japan just across a narrow strait.

A position that has made Korea both a cultural bridge

and a focal point for rival powers.

Today, South Korea covers over 38,000 square miles

with more than 52 million people

packed into one of the world's most densely populated nations.

In 1910, Japan seized control of Korea,

erasing its sovereignty for the next 35 years.

After Japan's surrender to Allied forces in 1945,

Korea was divided into Soviet and American

zones of occupation.

Two rival regimes emerged in 1948.

North Korea with its capital in Pyongyang,

and South Korea with its capital in Seoul.

Two years later, the Korean War erupted,

leaving at least two and a half million people dead.

The armistice of 1953 ended the fighting,

but didn't formally end the war.

And the peninsula remains divided to this day.

Devastated by war, Seoul was rapidly rebuilt

as waves of refugees and workers poured in.

In the decades that followed,

South Korea's rise as one of Asia's "Four Tigers"

turned the capital into a metropolis

of roughly 10 million.

Today, it anchors the nation's political power,

economic strength, and cultural life.

In September of 2023, a hidden underground space

beneath Seoul Plaza opens to the public

for the first time in 40 years.

Beneath CitiStar Mall,

Seoul's first underground shopping center,

lies a vast chamber.

It's about 43 feet underground,

just above the tracks of subway Line 2,

stretching between two stations, City Hall and Euljiro 1-ga.

The tunnel measures nearly 1,100 feet long

and just over 30 feet wide.

Altogether, it spans over 34,000 square feet.

Above this chamber, there's a drainage system,

and for decades water has dripped from the ceiling.

Over time, those steady drips have built a stalagmite,

a mineral column that rises from the floor,

gradually building upward

as each drop deposits a thin layer of calcium carbonate.

Despite its massive scale,

we don't know exactly why this chamber was built.

So, how does a space like this get constructed

in the middle of the city

then stay hidden from public view for so long?

What function was it meant to serve?

In the 1960s and '70s,

Seoul became the engine of South Korea's transformation

as mayors pursued urban planning

with the discipline of a wartime campaign.

But this was also a period of escalating tension

with North Korea, when even everyday spaces could be shaped

by the logic of defense.

After incidents like the 1976 murders

of two US officers

and the discovery of secret infiltration tunnels

from the north, Seoul began building underground shelters

and even designing some public spaces

with emergency use in mind.

So could the chamber beneath Seoul Plaza

have been part of that strategy?

Maybe it was a place to protect its citizens

or government officials in the event of an attack.

Seoul's explosive population growth

drove rapid urbanization and industrial expansion.

Ex-military mayors pushed sweeping redevelopment.

They expanded Seoul's boundaries,

built expressways and large-scale apartment complexes,

and created new towns in the city's south,

considered safer from attack.

In this era, urban planning wasn't just about

establishing a global presence,

it was intertwined with national security.

Tensions between north and south

were already high when a new threat emerged underground,

roughly 30 miles north of Seoul Plaza.

In 1978, authorities uncovered the so-called

"Third Tunnel of Aggression," the third such passage

discovered beneath the Demilitarized Zone since 1974.

It extended over 1,400 feet into South Korea

and was believed to stretch nearly 4,000 feet

back into North Korea.

Carved nearly 240 feet below ground,

and measuring about 6.5 feet high and wide,

it was large enough for military vehicles,

field guns, even tanks.

Experts estimated as many as 30,000 troops

could have passed through every hour.

Adding to the tension was the fact that the tunnel

opened toward the Munsan Corridor.

That's the same route used by North Korean forces

to reach Seoul in 1950.

Back then the US called it an "act of aggression."

But to South Korea, it was just evidence that the North

had never really abandoned its policy

of reunification by war.

The discovery also underscored a sobering reality:

the capital, which lies roughly 25 miles

from the Demilitarized Zone,

was still within easy reach of attack.

In that climate, it made sense

for Seoul to look underground for its own defenses.

Perhaps the tunnel under Seoul Plaza

was part of that response.

In 2005, construction workers in Yeouido,

just three and a half miles from Seoul Plaza,

were building a new bus station

when they uncovered what looked like a hollow void.

Further investigation revealed

it was actually a deliberately built bunker,

reportedly with no official records

to explain its existence.

The bunker's layout consists of two zones:

a living quarter of over 700 square feet,

complete with a sofa, shower, and bathroom,

and a sprawling machine room covering over 6,000 square feet.

These features suggest that it was intended

for a small number of VIPs.

Its construction appears to date to a period

of renewed Cold War tension.

Aerial photos from 1977 reveal what seemed to be its doors,

while none were present in images from 1976.

It sits directly beneath the raised platform

from which President Park Chung-hee would watch

military parades staged to project

South Korea's strength to the North.

And so many believe the bunker was built

for him and his bodyguards as a secure refuge

in the event of an attack.

The location and the general vibe of the bunker

at Yeouido point very clearly to a government function.

But the Seoul Plaza chamber is different.

It's way bigger, it's way less defined,

and it's just harder to explain.

There's no evidence to suggest it was built

to protect government officials or even civilians,

so maybe we've been barking up the wrong tree altogether.

But if so, what was it built for?

Not all interpretations

center on defense.

Some see the chamber as a reflection of South Korea's

own political landscape.

The Korean Central Intelligence Agency

was once arguably the most powerful institution

in South Korea.

Created in 1961 with American support,

one US official described it

as "a combination of the Gestapo and the Soviet KGB,"

reflecting the scale of its authority and methods.

If the agency could dominate politics,

intimidate communities abroad, and operate with such secrecy,

could a hidden chamber in central Seoul

have served as part of its operations?

By the early 1970s, the KCIA's reach was absolute.

It was accused of extorting money from businessmen,

abducting dissidents, torturing students

on fabricated espionage charges,

and later even engineering the 1987 bombing

of a Korean Air flight that killed 115 people.

In that climate, the idea that underground facilities

might have been built for intelligence use

really isn't far-fetched.

Less than a mile away, at the base of Namsan,

a scenic tree-covered peak in the heart of Seoul,

the KCIA's operations in their own facility's basement

show how subterranean spaces in Seoul

have served far darker purposes.

The KCIA headquarters on Namsan opened in 1973,

the same year a Seoul National University law professor died

while in the agency's custody.

Officials claimed he had confessed to being

a North Korean spy and jumped from a window.

But in the year 2000,

South Korea passed a law to honor,

and in some cases, compensate the people who took part

in the country's democracy movement,

creating a commission to review individual claims.

And that commission later concluded

that the allegation was fabricated

and that he had most likely been thrown from the building

or even tortured to death beforehand.

Possibly the first victim inside the new headquarters.

Namsan soon became synonymous

with state repression.

In South Korea's post-war authoritarian years,

"going to Namsan" meant ending up in KCIA custody,

often for involvement in pro-democracy activities

where torture was common.

The KCIA's record leaves little doubt

about its capacity for secrecy and abuse.

Its power radiated from the Namsan headquarters,

while abroad, its agents operated through embassies,

consulates, and front organizations.

But nothing in the public record suggests that it used

the vast hidden chamber beneath Seoul Plaza for its operations,

which opens up other possibilities

about its true purpose.

The official explanation

is the most straightforward and the least sensational.

When Seoul began building its subway

in the early 1970s, construction methods were very different

from what we see today.

Could the chamber beneath Seoul Plaza

simply be a byproduct of that process?

The evidence does line up.

The chamber lies right between Euljiro 1-ga

and City Hall stations.

And during the construction of Line 2,

when it's believed this underground space was created,

crews were digging down from the surface

instead of boring a tunnel in from the side,

which is how these things are done today.

So officials believe that when Euljiro 1-ga station

opened in 1983, this leftover space got sealed off

and then just remained hidden for more than four decades.

Over 6,700 miles across the Pacific,

in Cincinnati, Ohio, a similar underground void

tells its own story

about a subway line that never came to be.

In the early 20th century,

Cincinnati set out to build a 16-mile rapid transit loop

to serve its booming population.

By 1923, two miles of the subway tunnels were completed

to a spot just north of the Western Hills Viaduct

with a short tunnel running beneath Hopple Street

as part of the city's grand plan to modernize its transit system.

But costs spiraled after World War I.

Funds dried up, and planning was scaled back.

By 1929, the project was abandoned.

Tracks were never laid,

and crucial links to the system never finished.

The tunnels were sealed off and ultimately sidelined

by the Mill Creek Expressway, today's I-75.

Over the years, the abandoned subway was reimagined

for everything from fallout shelters

to underground wineries.

But in the end, it remained what it had always been,

a relic of unfinished planning.

The official explanation in Seoul

points to leftover subway construction,

and it makes sense.

With more than 65% of the land covered by mountains,

tunneling has become unavoidable for railroads, freeways,

subways, and the utility networks

buried beneath South Korea's cities.

The chamber under Seoul Plaza may simply be one of them;

an ordinary remnant of extraordinary infrastructure.

Hidden for decades,

the chamber beneath Seoul Plaza is now in plain view--

a reminder that even the most familiar urban landscapes

can contain histories we're only just beginning to uncover.

175 miles northwest of Warsaw,

where the Vistula River meets the Baltic Sea,

Gdansk has endured for centuries as a city

defined by commerce, conquest, and resilience.

In 1260, Gdansk secured municipal autonomy,

granting merchants the freedom to expand their trade.

Its position at the mouth of the Vistula

made it Poland's main outlet for grain and timber,

tying the city directly into northern Europe's trade routes.

In 1308, the Teutonic Knights seized Gdansk.

Invited east decades earlier,

the German Catholic military order had already carved out

a state in Prussia with papal and imperial backing.

Their conquest of the city

shifted the balance of power across the Baltic.

From Gdansk, they ruled more than a century

until King Casimir IV reclaimed it in 1466 after a 13-year war.

Casimir restored broad civic privileges,

fueling prosperity.

By the 18th century,

Gdansk could become the Baltic's leading port,

home to 77,000 people

and exporting over 200,000 tons of grain each year.

But even in modern times,

the fortunes of Gdansk rose and fell with conflict.

It was remade as the Free City of Danzig after World War I,

absorbed into Nazi Germany in 1939,

reduced to ruins in 1945,

and later rebuilt.

In July of 2025,

excavations beneath the site of a former ice cream shop

in the center of Gdansk uncover traces of a medieval past

long hidden beneath the city.

The first discovery was a limestone slab,

thought to be a tombstone about 60 inches long,

carved with the image of a man in full chainmail armor.

He's gripping a sword in his right hand,

a shield in his left hand,

with boots and leggings encasing his legs.

Monuments of this kind are exceptionally rare

from medieval Poland,

where tombstones almost never depicted the deceased

in such vivid detail.

The slab was lifted,

and after two more days of excavation,

they found a coffin below.

Inside lay the skeleton of a man,

surrounded by 23 field stones

carefully arranged in a rectangle.

Preliminary analysis showed

that he was about 40 years old at death

and stood between 5'6" and 5'9",

close to the average stature for men in medieval Gdansk.

The grave lies within a larger excavation zone,

spanning nearly 11,000 square feet,

which has uncovered traces of the city's earliest history--

wooden cottages, a 12th century timber street,

and Gdansk's first church,

built around 1140 in the form of a Greek cross.

The slab dates to the late 13th or early 14th century,

and even after centuries underground,

the outlines of the armor, sword, and shield

remain strikingly well preserved--

a monument to a man of clear status whose identity is lost.

So, who was he?

Why was he buried here?

And what can his burial reveal about the forces

that shaped the city at its beginnings?

In a city where wealth once flowed

through merchant hands, the tomb may reflect the ambitions

of a man who blurred the line between commerce and chivalry.

After the mid-15th century,

Gdansk was dominated by a merchant patriciate--

families who controlled trade, held civic office,

and displayed symbols of elite status.

They worked to secure shipping routes, guard against pirates,

and manage commerce,

competing directly with English and Dutch rivals.

Could this burial belong to one of them?

The slab itself is a major clue.

It was carved from Gotland limestone,

an expensive material that was imported from the Swedish island

at the heart of Baltic Exchange.

That kind of stone would have reached Gdansk

through trade routes, suggesting that the man in this grave

had direct access to the networks

of the ruling merchant class.

Over 800 miles northwest

on the Scottish island of Unst, another site shows

how merchants marked their presence far from home.

In the chapel ruins at Lunda Wick,

a weathered imported slab still honors a German merchant

who traded there for more than half a century.

Its inscription lists his name, city, and profession;

a grave that doubles as a statement

of mercantile identity.

In Gdansk, the pattern is different.

The knight's effigy bears no merchant's seal,

no inscription, no mark of trade;

only the imagery of sword, shield, and armor.

Nearly 115 miles south of Gdansk,

in the Kuyavia region of north-central Poland,

archaeologists uncovered a cemetery

of several dozen chamber graves

dating to the late 10th and early 11th centuries.

Four rows of graves contained the remains of 14 men,

21 women, and 14 children.

Each lay within a wooden box reinforced by iron fittings

and lined with fabric,

with some graves marked by larger rectangular enclosures

that may have been fences, or houses of the dead.

Alongside them, richly furnished cenotaphs

added further evidence of high status.

These burials were filled with remarkable items:

weapons, jewelry, coins, and ornaments of high quality.

Women were laid to rest with necklaces of glass beads,

gold foil beads, precious stones, and silver.

Two silver amulet containers, one engraved with a bird,

stand out as truly spectacular finds.

The discovery of silk fragments,

likely brought from as far away as China,

shows just how far

the community's trade connections reached.

Weapons in the men's graves--

Viking swords, a pickaxe,

and single-edged Langseax blades,

which were long, straight-edged knives used in battle

and as markers of status--

reveal a warrior elite whose funeral rites and equipment

marked them as high-status settlers.

The most striking case is a young man

buried with a silver-inlaid ceremonial sword

bearing a Rurikid tamga,

a symbol of the noble lineage that ruled the Land of the Rus',

which is evidence of far-reaching ties.

At this site, we see evidence of trade connections,

where wealth was displayed through weapons,

ornaments, and foreign imports.

But in Gdansk, there are no weapons, no jewelry, no silks,

only the carved image of a knight.

That absence makes it less likely

he was a wealthy merchant, and instead, opens the possibility

that his identity was defined in other ways.

Long before merchants and crusaders

left their mark on Gdansk,

power rested in the hands of a native dynasty.

The Sobieslawice Dynasty emerged in Gdansk

in the 12th and 13th century, ruling for nearly a century.

Its founder began as a governor,

but from 1227, his heirs styled themselves as dukes,

princes in their own right.

Could this have been a duke of their dynasty?

Excavations around the slab uncovered layers

of early settlement-- timber cottages,

a street built from 18 successive layers of wood,

and nearly 300 burials.

Only eight of those graves had stone markers,

and the knight's was by far the most elaborate.

That distinction suggests elite rank in a modest cemetery,

consistent with a dynastic identity.

Most members of the Sobieslawice Dynasty were buried

in a monastery they found at Oliwa,

but their original graves were destroyed several times

by fire and war.

That loss makes the Gdansk effigy all the more significant.

If it belonged to one of their princes,

it could be the earliest authentic ducal monument

still tied to the dynasty.

In 2018, a burial chest was discovered

hidden in a storeroom,

walled up inside St. Stephen's Church

at the Czech city of Olomouc's Hradisko Monastery,

around 330 miles southwest of Gdansk.

Decorated with elaborate artwork,

it held the skeletal remains of seven members

of the Premyslid Dynasty.

These were princes and princesses

who ruled Bohemia and Moravia from the 9th to 14th centuries.

Their identities were confirmed

only after DNA and radiocarbon testing.

The Sobieslawice princes of Gdansk

belong to the same medieval world,

and both groups' original tombs have been destroyed over time

by disaster or conflict.

But in Gdansk, the difficulty is twofold.

The effigy bears no name or inscription,

and it lies outside the dynasty's

known necropolis of Oliwa.

Its stark military imagery may instead hint at another power

that would soon dominate the city.

The tombstone may reflect status,

but its stark simplicity could connect

to Gdansk's most infamous occupiers.

After a campaign of expansion,

the Teutonic Order carved out a militarized state in Prussia.

In 1308, the Teutonic Knights seized Gdansk

in a brutal massacre, placing the city under their rule.

Could the man in this grave have once belonged to their ranks?

The conquest of 1308 gave the order direct control

over eastern Pomerania.

From Gdansk, they expanded deeper into Prussia,

building castles, churches, and monasteries.

A high-status burial from this moment of transition

would fit within the order's sudden,

violent presence in the city.

In the early 14th century,

Teutonic Knights in Gdansk swore vows

of poverty, chastity, and obedience.

A lone stone tool marked with martial symbolism

but devoid of goods

is exactly what we might expect of their burials.

The order also drew guest crusaders

from across Europe.

Nobles would join seasonal crusading campaigns

known as reysen

against Poland and Lithuania.

Many would have died on campaign far from their homelands.

With so many foreign knights passing through Gdansk,

it is possible that one was buried here.

Less than 30 miles southeast of Gdansk,

in Malbork, the Teutonic Order built its greatest fortress,

Malbork Castle.

Beneath it, the Chapel of St. Anne

shows how they buried their most powerful men.

The Chapel of St. Anne was likely built

in the 14th century as the burial place

for the Grand Masters of the Teutonic Order.

Dietrich von Altenburg was the first Grand Master

to be interred beneath its floor in 1341.

Ten of his successors were buried here, too,

making it the order's symbolic necropolis.

Ordinary knight burials were very different.

The Teutonic rule banned personal seals, coats of arms,

and ostentatious monuments.

Even clothing and equipment were tightly regulated.

Against that discipline, a solitary effigy

with only military imagery fits:

not a grand master celebrated in ritual,

but perhaps a single knight remembered in the simplest way.

Researchers are scanning the effigy in 3D

and testing the bones through chemical and genetic analysis,

aiming to uncover who this knight was and how he lived.

They even plan a facial reconstruction from the skull,

so the so-called Gdansk Lancelot

may soon be seen as he once appeared in life.

Beneath the streets of Gdansk,

the carved tomb of the night

carries the weight of a city's beginnings;

a trace of power preserved, but never fully explained.

In southern England, just outside Greater London,

is the ceremonial county of Buckinghamshire.

This part of Britain

has seen centuries of human history.

People have found evidence of Neolithic

and Bronze Age occupation across Buckinghamshire.

The hillfort at Ivinghoe Beacon was likely occupied

long before the Romans ever invaded.

But after that invasion,

Rome began construction on Watling Road,

which would ultimately connect this whole region

to what would later become London.

Buckinghamshire's more recent history

highlights British determination and perseverance.

In World War II, it was here that the Allied codebreakers

managed to crack the German Enigma Codes,

which helped bring the war to a close much sooner.

But it hasn't always been easy for Buckinghamshire

to hang on to its physical history.

One building lost to the past is St. Mary's Church

in the village of Stoke Mandeville.

Demolished in 1966,

St. Mary's rubble sits undisturbed until 2021,

when the city must make room

for a new national high-speed railway.

But prior to its removal,

researchers conducting a routine archaeological survey

of the site discover much more than they bargained for.

Beneath the foundation of the church,

another structure emerged from the earth and rock.

There were the foundations of a smaller, square-shaped building,

possibly a tower of some kind.

When the surrounding ditch was excavated,

some incredible artifacts were unearthed:

three portrait busts made of stone.

This site was like an archaeological nesting doll,

each layer presenting a new mystery.

The busts depict an adult male, an adult female,

and an additional head

that seems to be that of a young child.

But what's weird is that the adult busts appear to have been

decapitated before they were buried.

There are clean breaks at the necks.

And there's something else.

The remnants of a hexagonal jug made of glass.

Who put all these items here and what was this place?

The St. Mary's site is a multi-layered discovery,

with each stratum offering its own piece of British history.

We know that St. Mary's was built in 1080 CE,

shortly after the Norman conquest.

But the style of the busts are indicative

of early Roman sculpture,

dating them sometime between the 1st and 5th century.

During this time, the region was dotted

with large Roman farming estates.

Agriculture was a major driver of the economy.

The nearby Roman town of Magiovinium may have been

the location of a garrison and a Roman fort.

Magiovinium also shows evidence of multiple cemeteries.

People likely came here to bury their dead.

But the shards of the hexagonal glass jug

complicate the historical picture.

Jugs like this were often used as funerary vessels

for flasks of holy oil.

So what's it doing here?

Why was this vessel buried in a ditch

alongside these Roman sculptures?

Approximately 50 miles from the St. Mary's site

in Kent, near the town of Eynsford,

is the Lullingstone Villa residence,

where similar high-quality portrait sculptures

were discovered in 1949 by G.W. Meates and others.

The Lullingstone residents had two busts

made of marble, possibly depicting a man and his father,

and they were found

in the building's so-called "cult room."

So, maybe the sculptures under St. Mary's

had a similar spiritual meaning.

The stone busts were likely commissioned

by someone of great wealth and influence,

which further supports the notion

that many Roman inhabitants from this area

were from an affluent class.

These are families that could afford a statue

carved by skilled artisans, like the ones found under St. Mary's.

But why would a private residence be built

on top of this natural mound of dirt?

So far, nothing has tied these busts or the glass vessel

directly to a neighboring villa.

The remnants of plaster and the roof tiles suggest

that the busts and the glass

were likely buried during a demolition.

But a demolition of what?

The building's location may be the key

to understanding its purpose.

Natural mounds were the go-to locations

for ancient peoples when it came to choosing a burial site

or ceremonial center.

The circular ditch surrounding the site is also a common trait

of an Iron Age temenos--

an enclosure that was designed to separate the outside world

from a sacred location.

It's not hard to imagine this site being repurposed

under Roman authority as a temple for pagan rituals.

The busts in this context could be deities,

or they could be family portraits

of the temple's wealthy patrons.

As Christianity spread, the temple may have been destroyed

along with the statues and the glass vessel.

That could explain the seemingly ritualistic

severing of the stone heads

that may have been a way to neutralize a symbol of power.

In 1979, about 65 miles away

from the dig at Saint Mary's,

in the village of Uley in Gloucester,

a cult statue from the second century

was pulled from the ruins of a temple

built to honor the Roman god Mercury.

The limestone bust, which was a portrait of Mercury,

had its nose and lips damaged in antiquity,

but the head itself was found deliberately buried,

which could have happened

once the temple had been shuttered or demolished.

This ritual burial of artifacts

is called a structured deposition.

It was common for Christian churches to be built

on top of former temples, a signal to all that a new faith

had taken root in the community and supplanted the old one.

In the case of the St. Mary's site,

the Norman church was built directly on top

of the Roman rubble with no intervening soil in between.

Demolition of the Roman structure appears to have been

followed almost immediately by the construction of the church.

The surrounding ditch does strongly suggest

this was a sacred site for the Romans.

But the realistic style of portraiture that we see

in these three busts is more characteristic

of a commemorative statue than a spiritual idol.

So yes, this was likely a sacred space, but for what?

There is another discovery

within the Roman rubble that suggests

this mysterious building had a special purpose.

Within all the dust and debris,

the excavation unearthed a bunch of Roman cremation urns.

Those items suggest that the Roman church

was built on top of a Roman mausoleum.

Again, the severing of the heads on these busts

is very symbolic.

Within the context of the mausoleum,

these decapitations could tell a story of a family undone

by the fall of Roman Britain.

While there's no evidence

of any formal inhumations present at the site,

the urn suggests that cremation

was the primary funerary ritual here.

And the family depicted in the stone portraits

were likely the occupants of the tomb.

But there are still questions:

Who were this man, woman, and child?

If they represent a family, we can infer a lot

about their wealth and social status,

but we still don't know their identities.

Without any inscription, they remain anonymous.

The incoming high-speed railway

is but the latest chapter in the ongoing story

of the multi-layered historical site

beneath St. Mary's Church,

one that may still contain hidden secrets from the past.

In the eastern end of Los Angeles, California,

about seven miles southeast of Hollywood,

is the historic neighborhood of Lincoln Heights.

Lincoln Heights is the oldest suburb of Los Angeles.

In the late 1800s,

one of the city's first horse-drawn streetcars

ran through its streets.

Due to the neighborhood's proximity to downtown,

early residents here were primarily commuters,

but Lincoln Heights quickly grew into a community of its own,

attracting manufacturing companies

and establishing both a nearby hospital and a library.

In the early 20th century,

Lincoln Heights had numerous attractions

that made it a destination for Angelenos.

Families could visit Lincoln Park,

one of the oldest parks in the city,

and other amusements like a merry-go-round

and miniature railroad.

Animal exhibits were definitely a major draw here.

The Selig Zoo near the park

preceded the Los Angeles Zoo by 50 years.

Lincoln Heights also featured the California Alligator Farm

and even something called the Los Angeles Ostrich Farm.

In 1931, planning is underway for an orchard

on Lincoln Heights' Flat Top Hill,

and a plumber at the site discovers something unusual

while digging a trench for the irrigation system.

It looked like a vertebra

from some kind of very big creature.

So a team from the Natural History Museum

was brought in to investigate.

They found a significant number of bones

buried under the ground.

The remains included a large skull and lower jaw,

a left shoulder blade, and a series of 22 vertebrae.

What was this thing?

3,000 pounds of bones and sediment are removed

from the pit for further study.

And using a process called relative dating,

the rock layers in which the skeleton was entombed

are used to determine the age of the fossil.

This area was part of what's called

the Modelo Formation,

which dates to the Middle to Late Miocene Epoch,

between 8 and 16 million years ago.

Cross-referencing this data with other fossils from California,

it was determined this animal arrived

at its final resting place over 10 million years ago.

This era was defined by cooler global temperatures

after the warmer Early Miocene.

It was a volatile period in the planet's history,

with dramatic geological changes

caused by shifting tectonic plates.

Tropical forests declined while grasslands expanded.

Geological studies of the Modelo Formation

show that it was submerged in the ocean

during this period at a depth of about 3,200 feet.

The fossilized remains are sent

for laboratory analysis,

and the results leave researchers stunned.

They're from a previously

undiscovered species of whale.

This incredible specimen is what's called a holotype,

meaning it's the only one of its kind anywhere in the world.

It was given the name Mixocetus elysius,

which was a reference to the creature's whale-like features

and the geological layer it was found in,

the Elysian Park sandstone.

Based on the measurements

of the skull and vertebrae,

it's estimated this whale was approximately 32 feet long.

During this period,

it would have been one of the largest in the world.

So its discovery raised a couple of key questions.

How did an animal of this size end up under the slopes

of Flat Top Hill in Lincoln Heights?

And how did this creature die?

One of the most terrifying sea monsters

from prehistoric times was a giant shark known as megalodon.

Sometimes 60 feet in length and weighing as much as 50 tons,

the megalodon was the largest shark that ever lived.

It dominated the ocean as the apex predator of its era.

So, could the Lincoln whale have been a victim

of a megalodon attack?

Other whale fossil discoveries

suggest this could be a possibility.

In 2022, fossilized whale vertebrae recovered

along the Maryland shores of the Chesapeake Bay,

showed evidence of a massive compression fracture.

The fossils were estimated

to be about 15 million years old.

And evidence showed that the whale's backbone

had been forcibly bent into a tight curve

that caused one of the vertebrae to smash into another one.

That might actually be a predation injury.

And what might have caused that?

Well, helpfully, the tooth of a megalodon

was found with the remains.

In fact, it was touching one of the vertebrae.

So is that what killed our whale?

Sharks use a variety of techniques

to disable their prey,

so if a megalodon had chosen the Lincoln Heights whale

as its prey, it could have used one of several methods,

including ramming it from below

or biting off its tail flukes or pectoral fins,

neither of which were found with the fossil.

The skull of the Lincoln Heights whale

did show some trauma near the jawbone,

but a 2024 report from the Natural History Museum

stated there was no evidence of any megalodon teeth

in the whale's skull, vertebrae, or shoulder bones.

Yes, a megalodon could have overcome the whale

without biting it, but there's simply no concrete proof

that the Lincoln Heights whale encountered a giant shark.

If the whale wasn't annihilated

by a vicious predator,

it may have been the victim of a silent killer.

Some of the most insidious and lethal life forms

on the California coast are harmful algae blooms, or HAB.

The single-celled algae, Pseudo-nitzschia,

produce a deadly toxin that can attack

the central nervous system of marine mammals.

Those who ingest the algae can experience seizures,

disorientation, fatigue, and ultimately death

from neurological damage or drowning.

The Cerro Ballena fossil site

in Chile's Atacama Desert is a strong point of comparison.

About 40 fossilized prehistoric whale skeletons

from the Late Miocene lay among remains

from seals and other marine vertebrates.

The four distinct layers of fossils were attributed

to recurring mass die-offs,

resulting from the presence

of large-scale harmful algae blooms.

Studying an area like Cerro Ballena

with multiple fossils deposited over many millions of years

allows for a much more robust theory

to develop around a mass death.

But evidence of one whale carcass is much less conclusive.

Ultimately, it may be next to impossible

to uncover physical or chemical evidence

on the Lincoln Heights fossil

that proves it had ingested toxic algae.

The greatest threat to the whale may have been

the volatile habitat along the California coast.

During the Middle to Late Miocene period,

the tectonic plates under California

were undergoing an incredible transformation.

The Los Angeles basin was especially active,

making catastrophic submarine landslides

a frequent occurrence.

Paleontologists believe that after

the whale perished,

it was buried in a violent underwater landslide,

which would have immediately concealed the carcass

from large scavengers

and helped preserve it for millennia.

In 1976, a baleen whale fossil from the Miocene period,

excavated in Poland, was reported to have been found

in a similar state of preservation.

Its death was attributed to rapid burial

by quickly accumulating sediment.

This supports the theory that the Lincoln Heights whale

could have died from a turbulent undersea event.

The Modelo Formation, in which the whale fossil was found,

is largely made up of sediments

deposited by currents in a deep sea environment.

Over the subsequent 11 million years,

great shifts in tectonic pressure

along the California coast raised the seabed by 500 feet,

pushing it 20 miles inland to form the hills of Los Angeles,

where the Lincoln Heights whale would eventually be found.

California's shifting geological forces

may help explain the whale's death and unusual burial,

but many unanswered questions remain.

While it's possible the Lincoln Heights whale

was subsumed by a geological event,

the true cause of death remains a mystery.

Old age, disease, or starvation

may have played a factor in its demise.

More discoveries of any fossil from the Modelo Formation

is gonna help paint a clearer picture of what life was like

before this whale ever died.

One of the biggest unknowns

is why this whale fossil remains the only specimen of its species

ever discovered.

With future excavations, additional discoveries

will hopefully help us better study the animal, its habitat,

and its history during the Miocene.

For now, Mixocetus elysius

is one of one;

a single piece of a larger historical puzzle

that is yet to be fully understood.