Welcome to Ringworld, an intermediate step between Dyson Spheres and planets. The gravitational force created by a rotation on its axis of 770 miles per second means no need for a roof. Walls 1,000 miles high at each rim will let in the sun and prevent much air from escaping. Larry Niven's novel Ringworld is the winner of the 1970 Hugo Award for Best Novel.

Come back to the Ringworld - the most astonishing feat of engineering ever encountered. A place of untold technological wonders, home to myriad humanoid races, and world of some of the most beloved science fiction stories ever written.

The human Louis Wu; the puppeteer known as the Hindmost; Acolyte, son of the Kzin called Chmeee: legendary beings brought together once again in the defense of the Ringworld. Something is going on with the protectors.

The Ringworld is a landmark engineering achievement, a flat band 3-million-times the surface area of Earth, encircling a distant star. Home to trillions of inhabitants, not all of which are human, and host to amazing technological wonders, the Ringworld is unique in all of the universe.

For decades, the spacefaring species of known space have battled over the largest artifact - and grandest prize - in the galaxy: the all-but-limitless resources and technology of the Ringworld. Now, without warning, the Ringworld has vanished, leaving behind three rival war fleets. If the fallen civilization of the Ringworld can no longer be despoiled of its secrets, the puppeteers will be forced to surrender theirs - everyone knows that they are cowards. But the crises converging upon the trillion puppeteers of the Fleet of Worlds go far beyond even the onrushing armadas.

Covert agent Sigmund Ausfaller is Earth's secret weapon, humanity's best defense against all conspiracies, real and imaginary, and all foes both human and alien. Who better than a brilliant paranoid to expose the devious plots of others?

But Sigmund may finally have met his match in Nessus, representative of the secretive Puppeteers, the elder race who wield vastly superior technologies.

The Mote In God's Eye is their acknowledged masterpiece, an epic novel of mankind's first encounter with alien life that transcends the genre. No lesser an authority than Robert A. Heinlein called it "possibly the finest science fiction novel I have ever read".

After forming a coalition of human resistance against the enemy invasion, Dalinar Kholin and his Knights Radiant have spent a year fighting a protracted, brutal war. Neither side has gained an advantage, and the threat of a betrayal by Dalinar’s crafty ally Taravangian looms over every strategic move. Now, as new technological discoveries by Navani Kholin’s scholars begin to change the face of the war, the enemy prepares a bold and dangerous operation. The arms race that follows will challenge the very core of the Radiant ideals.

Civil war looms in the Bobiverse in this brand-new, epic-length adventure by Audible number one best seller Dennis E. Taylor. More than a hundred years ago, Bender set out for the stars and was never heard from again. There has been no trace of him despite numerous searches by his clone-mates. Now Bob is determined to organize an expedition to learn Bender’s fate - whatever the cost. But nothing is ever simple in the Bobiverse. Bob’s descendants are out to the 24th generation now, and replicative drift has produced individuals who can barely be considered Bobs anymore.

Fleet of Worlds takes a closer look at Human-Puppeteer (Citizen) relations and the events leading up to Niven's first Ringworld novel. Kirsten Quinn-Kovacks is among the best and brightest of her people. She gratefully serves the gentle race that rescued her ancestors from a dying starship, gave them a world, and nurtures them still. If only the Citizens knew where Kirsten's people came from.

The newly liberated humans of the Fleet of Worlds and Sigmund Ausfaller, who had been transported by the Puppeteers from Earth to the Fleet, must contend not only with the sly Puppeteers but also the threat of the Pak, a very smart and utterly ruthless species who are fleeing the exploding galactic core in an armada of ships at near light speed. The Pak are headed towards the Fleet of Worlds, having destroyed entire planets in their wake.