Rauros

The Anduin, after passing the Argonath and spreading into the long lake of Nen Hithoel, poured out at the lake's southern end around the island of Tol Brandir and fell over a cliff in a roar that could be heard for miles. These were the falls of Rauros, the golden-roaring spray, and they marked the end of the navigable river from the north. Below them the Anduin ran on through a stretch of rapids and then wound slowly across the marshy lowlands called the Wetwang, where the Entwash joined it, before flowing south to Cair Andros and Osgiliath.

Because the falls could not be run by boat, the Númenóreans of Gondor had cut a portage way, the North Stair, on the western side, by which boats could be carried down to the river below. It was old and overgrown by the end of the Third Age.

The falls were the northern limit of river travel in Gondor's days and the point at which any northern traveller had to choose the western road through Rohan or the eastern road towards Mordor. On February 26, 3019, after the breaking of the Fellowship, Aragorn, Legolas and Gimli laid Boromir in one of the Elven boats with his sword and the weapons of his enemies and let the current carry him over Rauros. The boat was not wrecked; Faramir saw it pass, whole and shining, down the river through Osgiliath many days later, and the horn of Gondor, cloven in two, was found washed up on the shores below the falls and brought to Denethor.

Rauros lay at the southern end of Nen Hithoel between Amon Hen and Amon Lhaw. The North Stair descended on the western bank. Below the falls the Anduin entered the Wetwang, and the Emyn Muil fell away on either side.