Seven Rivers of Ossir
- The River Gelion and its six tributaries.Seven rivers that flowed through Ossiriand, the land of the Green-elves west of the Blue Mountains. The most important of these was the Gelion, which flowed from the March of Maedhros in the far north, and formed the western border of Ossiriand.The other six rivers were tributaries of this large river, each stemming from a separate spring in the Blue Mountains, and flowing westward to empty into the Gelion. The northernmost of these was the Ascar, which rose in the mountains near Nogrod, and flowed beside the Dwarf-road to Sarn Athrad. South from the Ascar were the Thalos, the Legolin, the Brilthor and the Duilwen. Finally, the southernmost of the six was the River Adurant, in which the green island of Tol Galen stood.
J.R.R. Tolkien's Middle-earth glossary. MueRTe. 2003.