Ringworld

Hugo Award 1971, Nebula Award 1970, Locus Award 1971.

'The most energetic future history ever written' – The Encyclopedia of Science Fiction

Pierson's puppeteers, strange, three-legged, two-headed aliens, have discovered an immense structure in a hitherto unexplored part of the universe. Frightened of meeting the builders of such a structure, the puppeteers set about assembling a team consisting of two humans, a puppeteer and a kzin, an alien not unlike an eight-foot-tall, red-furred cat, to explore it.

The artefact is a vast circular ribbon of matter, some 180 million miles across, with a sun at its centre – the Ringworld. But the expedition goes disastrously wrong when the ship crashlands and its motley crew faces a trek across thousands of miles of the Ringworld's surface.