Ringworld series

The Ringworld series (1970–2012), by science fiction author Larry Niven, is a part of his Known Space set of stories. Its backdrop is the Ringworld, a giant artifact 600 million miles in circumference around a sun. The series is composed of five standalone science fiction novels, the original award-winning book and its four sequels:

Fate of Worlds is also a sequel to the four books of the Fleet of Worlds series, set in the same "Known Space" universe and all written by Niven and Edward M. Lerner:

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