The Ringworld series is a series of science fiction novels written by American author Larry Niven.
It is part of his Known Space series of stories.
Its backdrop is the Ringworld, a giant artifact 600 million miles in circumference circling a star.
The series is composed of four standalone science fiction novels, the original award-winning book and its three sequels: The companion novels to the Ringworld series are set in the same "Known Space" universe and all written by Niven and Edward M. Lerner: