Greylin.

River Greylin had its wells in Western Ered Mithrin. It was actually two streams 25 Miles apart joining each other about 20 Miles further South and running further 30 Miles until it with the contributing waters of river Langwell from Hithaeglir became Anduin. It was in the angle of Greylin and Langwell the people of Eorl the Young lived ( Later Rohirrims ) their chief dwelling Framsburg was located 10 -15 Miles East of the rivers outflow to Anduin / Langwell.