Mare Infinitus, sometimes abbreviated as "Mare-Eye," is a moon located within the WorldWeb of the Hegemony of Man. It is known for its globe-spanning ocean, which lacks islands or landmasses of any kind. It orbits an enormous sub-Jovian terrestrial planet.
Mare Infinitus' seawater is an unusual deep violet hue, resulting from the proliferation of a type of planktonic algae. It is one of the worlds located on the River Tethys; the farcaster portals comprising the Mare Infinitus section of the tour are buoyed and anchored in place.
Its waters contain a microorganism that causes severe infection in humans with injuries exposed to it. It grows inside the body "like fen fungus", branching out into the internal organs.
Visitors to Mare Infinitus looking over the horizon see what appear to be three moons, one of which looks like a great orange sphere that dominates the sky and dwarfs the other two smaller bodies rising over the turbulent violet waters. In fact, Mare Infinitus itself is the moon orbiting a near Jovian-sized rocky world. The rocky giant is described as covered by a dusty surface upon which rust-colored clouds move. There are brown blemishes on it like volcano flows, mountain ranges, a long valley like a scar, and a faint icefield at the north pole. The sub-jovian rocky planet was said to resemble Mars before terraforming.