Tanar Of Pellucidar by Edgar Rice Burroughs

A young warrior of the inner world of Pellucidar embarks on a bold campaign of rescue and revenge after his people and his beloved are threatened, cutting a swath through hostile tribes, prehistoric beasts, and treacherous strongholds; through daring raids, shifting alliances, and explorations of the strange, sunlit interior of the Earth he grows into a leader who ultimately confronts and overthrows his enemies, restores safety to his people, and secures love and honor amid the primeval wonders and dangers of Pellucidar.

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