WEBVTT

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Flanked by two powerful European nations,
the English Channel

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has long been one of the world’s 
most important maritime passages.

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Yet for most of its history,

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the channel’s rocky shores 
and stormy weather

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made crossing a dangerous prospect.

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Engineers of the early 1800's 
proposed numerous plans

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for spanning the 33 kilometer gap.

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Their designs included artificial islands 
linked by bridges,

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submerged tubes suspended 
from floating platforms,

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and an underwater passage more than twice 
the length of any existing tunnel.

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By the end of the century,

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this last proposal had captured 
European imagination.

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The invention 
of the tunnel boring machine

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and the discovery of a stable layer 
of chalk marl below the seabed

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made this fantastic tunnel 
more feasible.

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But the project’s most urgent obstacles 
were ones no engineer could solve.

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At the time,

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Britons viewed their geographic isolation 
as a strategic advantage,

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and fears about French invasion 
shut down plans for the tunnel.

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The rise of aerial warfare rendered 
these worries obsolete,

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but new economic concerns 
arose to replace them.

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Finally, 100 years after 
the initial excavation,

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the two countries 
reached an agreement—

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the tunnel would proceed 
with private funding.

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In 1985, a group 
of French and British companies

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invested the modern equivalent 
of 14 billion pounds,

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making the tunnel the most expensive 
infrastructure project to date.

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The design called 
for three separate tunnels—

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one for trains to France, 
one for trains to England,

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and one service tunnel between them.

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Alongside crossover chambers, 
emergency passages, and air ducts,

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this amounted to over 200 kilometers 
of tunnels.

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In 1988, workers began excavating 
from both sides,

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planning to meet in the middle.

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Early surveys of the French coast 
revealed the site was full of fault lines.

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These small cracks 
let water seep into the rock,

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so engineers had to develop 
waterproof boring machines.

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The British anticipated drier conditions, 
and forged ahead with regular borers.

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But only months into the work, water 
flooded in through undetected fissures.

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To drill in this wet chalk, 
the British had to use grout

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to seal the cracks 
created in the borer’s wake,

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and even work ahead of the main borer

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to reinforce the chalk 
about to be drilled.

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With these obstacles behind them, 
both teams began drilling at full speed.

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Boring machines weighing up to 1,300 tons 
drilled at nearly 3.5 meters per hour.

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As they dug, they installed lining rings 
to stabilize the tunnel behind them,

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making way for support wagons 
following each machine.

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Even at top speed, 
work had to proceed carefully.

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The chalk layer followed a winding path 
between unstable rock and clay,

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punctured by over 100 boring holes 
made by previous surveyors.

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Furthermore, both teams had 
to constantly check their coordinates

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to ensure they were on track to meet 
within 2 centimeters of each other.

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To maintain this delicate trajectory,

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the borers employed 
satellite positioning systems,

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as well as paleontologists 
who used excavated fossils

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to confirm they were at the right depth.

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During construction, 
the project employed over 13,000 people

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and cost the lives of ten workers.

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But after two and a half years 
of tunneling,

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the two sides finally made contact.

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British worker Graham Fagg 
emerged on the French side,

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becoming the first human to cross 
the channel by land since the Ice Age.

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There was still work to be done—

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from installing crossover chambers 
and pumping stations,

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to laying over a hundred miles of tracks, 
cables, and sensors.

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But on May 6, 1994, an opening ceremony 
marked the tunnel’s completion.

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Full public service began 
16 months later,

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with trains for passengers 
and rail shuttles for cars and trucks.

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Today, the Channel Tunnel services 
over 20 million passengers a year,

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transporting riders across the channel 
in just 35 minutes.

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Unfortunately, not everyone has 
the privilege of making this trip legally.

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Thousands of refugees have tried 
to enter Britain through the tunnel

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in sometimes fatal attempts.

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These tragedies have transformed 
the tunnel’s southern entrance

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into an ongoing site of conflict.

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Hopefully, the structure’s history 
can serve as a reminder

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that humanity is at their best 
when breaking down barriers.