Fantasy River Name Generator

Rivers carry the oldest names on any real map. Avon, Ouse, Esk, and Usk all just mean 'water' or 'river' in languages older than English, which is why fantasy rivers sound most convincing when they are short, ancient-seeming, and slightly opaque: the Anduin, the Isen, the Trident, the Rhoyne. A one- or two-syllable name with 'the' or 'River' in front of it will pass on almost any map.

English also gives you a set of smaller water words to grade rivers by size and region: burn and beck (Scottish and Northern English streams), brook and bourne (Southern), run and race (American and mill streams), fleet (a tidal creek), wash (a shallow crossing). Coldburn, Troutbeck, Sarnbrook, and Ebbfleet are the tributaries; the great river they feed deserves its own proper name. Descriptive compounds (the Greywater, the Blackwater Rush, the Milkwater) sit in between and are especially useful for rivers colored by glacier silt, peat, or blood.

Mythic rivers form a third register: the Styx, the Lethe, the Gjöll that borders the Norse underworld, or invented ones like the River of Souls and the River That Runs Backwards. Use one of these for the river that matters most to your plot, and let the rest be plain Sarn, Kell, and Ysk.