The river associated with the Paths of the Dead is Morthond, also called Blackroot. It rises beneath the White Mountains near the southern exit of the haunted passage and runs through Blackroot Vale in Gondor.
Aragorn, Legolas, Gimli, and the Grey Company emerge from the Paths of the Dead beside the river during the War of the Ring. The river’s source is connected with the caverns beneath the mountains, and its course continues southward through the vale before joining the Ringló.
Morthond is a Sindarin name meaning “black-root,” while Blackroot is its Common Speech equivalent. This creates a common source of confusion: both names refer to the same river, not two different waterways.
The river should not be confused with the Anduin, Gondor’s great eastern river, or the Isen, which flows through western Rohan. Celebrant is another name for the Silverlode, far to the north.