I remember reading a novel about the discovery of an ancient reptilian race discovered in a subterranean cave system. I thought it was written by Robert Silverberg but can't find it in his list of books. I think it was a YA novel. It was probably written in the 50s, 60s or early 70s.
closed as too broad by Adamant, QuestionAuthority, TheLethalCarrot, Valorum, Rand al'Thor♦ Aug 10 at 10:21
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