City Under the SeaIn the future humans may need to adapt to a life underwater. There will be many dangers. Scolding volcanic fluids and crushing pressures can kill the unwary. In some ways it's easier to live in space than underwater. We know more about the moon than the dark depths of our own planet.

The oceans are the Earth's final frontier. But we may be forced to take the plunge. And ever improving technology is making it possible. We may soon live as science-fiction writers have long imagined - under the sea.

With a host of problems threatening the Earth's surface, is underwater living a viable alternative? Meet the scientists who believe that permanently submerged colonies are not just possible, but imminent.

This is hypothetical challenge of housing 100 families below the ocean's surface and race to overcome obstacles such as bone-crushing pressures, ravaging storms, and scalding volcanic fluids to create self-sufficient underwater communities.

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