The Caves of Drach is a juvenile science fiction novel written by Hugh Walters and published in 1977.

[1] A multi-billionaire's grandson gets lost in the Caves of Drach in Majorca.

The expedition finds him in a huge and airy underground civilization peopled by practically immortal humanoid beings who hail from the stars and took refuge underground when a Terran Ice-age threatened.

The 'Cenobians' have a utopian civilization and avoid contact with the surface to keep it that way, and yet their advanced technology could bring an end to famine and disease.

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