Vaults are large underground bunkers that serve as a central part of the
Fallout computer game series. Built by Vault-Tec, these structures were each designed to keep 1,000 people safe from nuclear destruction and the effects of
fallout and radiation afterward. They were not intended, however, to protect the entire population of the
United States, as over 400,000 would be needed to provide safety to everyone. Rather, the vaults had a far more sinister purpose, which is discovered in
Fallout 2. The vaults were designed to comfortably host 1,000 people for 10 years after a nuclear apocalypse.
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