The river Poros was the largest of the Anduin's eastern tributaries. It arose high in the Ephel DĂșath (Mountains of Shadow), descended through a wide valley, and joined the Anduin near its delta.

The river formed a natural barrier between South Ithilien and the Harad Lands. It could only be forded at one point, the Crossings of Poros.
Encyclopedia entry originally written by atalante_star