Ringworld series

Winner of both the Hugo and Nebula Awards for Best Novel, Ringworld remains a favorite among science fiction readers.

The artifact is a vast circular ribbon of matter, some 180 million miles across, with a sun at its center. Pierson's puppeteers—strange, three-legged, two-headed aliens—discovered this "Ringworld" in a hitherto unexplored part of the galaxy. Curious about the immense structure, but frightened by the prospect of

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A cross-over conclusion to the Ringworld and Fleet of Worlds series finds the Puppeteers of the Fleet of Worlds targeted by rival war fleets after the disappearance of the Ringworld, prompting exiled Puppeteer Hindmost to draw on his knowledge of Ringworld technology to reclaim his power.