Protecting Their Air
The tunnels were also well ventilated. More than 15,000 air shifts were constructed throughout the tunnels. This ensured that there was always clean air for the inhabitants.
Protecting Their Air
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Living Underground
All of these developments ensured that the 20,000-strong population could live as normally as possible while in refuge. They wanted to life to go on as it would on the outside, for as long as they needed it to.
Living Underground
