Ringworld by Larry Niven (1970)

HaloIn my continuing exploration of many of the classics of speculative fiction, I read Larry Niven's Ringworld. If you're familiar at all with the Halo video game franchise, you know at least one thing this book inspired. The central feature is an artifact, a made world in the shape of an enormous ring. It surrounds a sun, spinning to simulate gravity, with high walls at the edges to keep air,