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Underworld

5 episodes 97%4KCC

3D scans expose Britain's deepest mysteries in vast, hostile caves.

Descend with expert cavers into Britain’s flooded passages, towering shafts, and hidden chambers as cutting-edge laser scanning turns darkness into precise 3D worlds. Along the way, the series uncovers how caves form, what they reveal about ancient fears and human history, and why discoveries are still being made beneath familiar landscapes. Sign up to see exploration and science meet where few people ever go.

Episode guide

5 episodes
1
1Great Britain
In Underworld: Great Britain the team examines the deepest shaft discovered in the UK – Titan. They hope a 3D scan can reveal its true size and secrets about its formation.
52 min
2
2Gibraltar
In Underworld: Gibraltar, the team learns more about the Rock’s caves and tunnels. At Gorham’s Cave, secrets are revealed about our Neanderthal cousins and their importance to the Ancient Greeks.
52 min
3
3Slovenia
Underworld: Slovenia is an adventure into Slovenia’s largest ice cave. The team scans the volume of ice, providing data for scientists to assess climate change.
52 min
4
4Belize
In Underworld: Belize the team discovers why the Maya Civilization vanished. In the cave of Actun Tunichil Muknal, they uncover the remains of human sacrifices. Professor Holley Moyes reveals how a drought caused the Maya to venture underground to make human sacrifices as they prayed for rains.
52 min
5
5China
Underworld: China uncovers the secrets of China’s giant caves. A team maps Cloud Ladder Hall, showing how its size creates an underground weather system.
52 min
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