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2,300 years ago,

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the rulers of Alexandria 
set out to fulfill

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one of humanity’s most audacious goals:

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to collect all the knowledge in the world 
under one roof.

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In its prime,

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the Library of Alexandria housed 
an unprecedented number of scrolls

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and attracted some of 
the Greek world’s greatest minds.

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But by the end of the 5th century CE,
the great library had vanished.

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Many believed it was destroyed 
in a catastrophic fire.

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The truth of the library’s rise 
and fall is much more complex.

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The idea for the library came 
from Alexander the Great.

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After establishing himself as a conqueror,

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the former student of Aristotle 
turned his attention

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to building an empire of knowledge 
headquartered in his namesake city.

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He died before construction began,

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but his successor, Ptolemy I,

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executed Alexander’s plans 
for a museum and library.

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Located in the royal district of the city,

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the Library of Alexandria

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may have been built 
with grand Hellenistic columns,

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native Egyptian influences,

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or a unique blend of the two--there are 
no surviving accounts of its architecture.

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We do know it had lecture halls, 
classrooms, and, of course, shelves.

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As soon as the building was complete,

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Ptolemy I began to fill it with
primarily Greek and Egyptian scrolls.

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He invited scholars to live 
and study in Alexandria at his expense.

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The library grew as they contributed 
their own manuscripts,

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but the rulers of Alexandria still wanted 
a copy of every book in the world.

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Luckily, Alexandria was a hub for ships
traveling through the Mediterranean.

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Ptolemy III instituted a policy requiring 
any ship that docked in Alexandria

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to turn over its books for copying.

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Once the Library’s scribes 
had duplicated the texts,

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they kept the originals 
and sent the copies back to the ships.

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Hired book hunters also scoured 
the Mediterranean

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in search of new texts,

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and the rulers of Alexandria attempted 
to quash rivals

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by ending all exports of the Egyptian 
papyrus used to make scrolls.

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These efforts brought hundreds 
of thousands of books to Alexandria.

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As the library grew,

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it became possible to find information 
on more subjects than ever before,

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but also much more difficult to find 
information on any specific subject.

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Luckily, a scholar named Callimachus of
Cyrene set to work on a solution,

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creating the pinakes,

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a 120-volume catalog 
of the library’s contents,

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the first of its kind.

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Using the pinakes,

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others were able to navigate 
the Library’s swelling collection.

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They made some astounding discoveries.

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1,600 years before Columbus set sail,

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Eratosthenes not only realized 
the earth was round,

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but calculated its circumference 
and diameter

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within a few miles of their actual size.

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Heron of Alexandria created 
the world’s first steam engine

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over a thousand years before

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it was finally reinvented during 
the Industrial Revolution.

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For about 300 years after its founding 
in 283 BCE, the library thrived.

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But then, in 48 BCE, Julius Caesar 
laid siege to Alexandria

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and set the ships in the harbor on fire.

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For years, scholars believed the library 
burned as the blaze spread into the city.

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It's possible the fire destroyed 
part of the sprawling collection,

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but we know from ancient writings

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that scholars continued to visit 
the library for centuries after the siege.

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Ultimately, the library slowly disappeared
as the city changed from Greek,

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to Roman,

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Christian,

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and eventually Muslim hands.

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Each new set of rulers viewed 
its contents as a threat

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rather than a source of pride.

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In 415 CE,

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the Christian rulers even had 
a mathematician named Hypatia

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murdered for studying 
the library’s ancient Greek texts,

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which they viewed as blasphemous.

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Though the Library of Alexandria 
and its countless texts are long gone,

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we’re still grappling 
with the best ways to collect,

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access,

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and preserve our knowledge.

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There’s more information available today

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and more advanced technology 
to preserve it,

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though we can’t know for sure

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that our digital archives 
will be more resistant to destruction

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than Alexandria’s ink and paper scrolls.

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And even if our reservoirs of knowledge 
are physically secure,

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they will still have to resist 
the more insidious forces

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that tore the library apart:

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fear of knowledge,

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and the arrogant belief 
that the past is obsolete.

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The difference is that, this time, 
we know what to prepare for.