Location from Hyperion by Dan Simmons
A river that flowed through farcaster portals across dozens of worlds — you could kayak through a portal on one planet and emerge on another, the ultimate symbol of the Web's seamless convenience.
The River Tethys was the WorldWeb's most spectacular feature — a waterway that flowed through farcaster portals on dozens of worlds, creating a continuous river across the galaxy. You could paddle a kayak through a portal on Renaissance Vector and emerge on Maui-Covenant under different stars. After the Fall, the farcaster portals went dead and the river was severed into disconnected segments on individual worlds. In the Endymion novels, the old farcaster portals along the Tethys still function sporadically — Aenea, Raul, and Bettik traveled through them to flee the Pax. The River Tethys represents what was lost in the Fall: the beauty and convenience of a connected civilization built on invisible exploitation.
A river that passes through farcaster portals — the water flows continuously but the landscape changes with each portal: tropical forest to arctic tundra to desert canyon in the span of kilometers. After the Fall, the portals went dead and the river exists only in segments on individual worlds.
Also known as: River Tethys, The Tethys