> Orbitals, while enormous (greater surface area than earth), are much smaller. The Culture novels do have Ringworld-sized rings as well, though. E.g. from Consider Phlebas, flying under the orbital Vavatch: "It was like flying upside-down over a planet made of metal; and of all the sights the galaxy held which were the result of conscious effort, it was one bested for what the Culture would call gawp value only by a big Ring, or a Sphere."
