The longest river of forochel, the mighty Lhúchir found its glacial sources at the feet of Mount Gundabad, some five hundred miles southeast of the shores of Sheltered Bay where it surrendered its waters at last to the sea. The Lhúchir got its name from Dîn Lhûg, the dragon-infested gap which separated the Misty Mountains from the Grey Mountains. Few worms of that region ranged far onto the Talath Uichel, and for this reason the Estiva Talven name for the river, the "Silverwater," bore no relation to the connotations of its Sindarin name, referring instead to its swift, glittering surface.
The cold, deep waters of the Lhúchir divided the Lakeland from the Herd Tundra (though the tundra lay on both sides of it). The Lumimiehet camped and made settlement all along both sides of it (the majority on the northern bank), fishing and hunting along the river, as well as using it for transportation. In winter, the river was a mass of grinding ice and deadly, frigid water. In early autumn, before the ice and winter predators posed a serious threat, many Lumimies villages on the southern banks were abandoned, and their inhabitants removed to winter with their neighbors farther north, since it was a simpler matter for fifty villagers to drive a wolf pack away than for ten. The river formed a convenient barrier between the Lumimiehet and the Angmarrim. Even long after the fall of Angmar, the Lumimiehet still kept the practice of moving to the northern banks of the river.
Lumimies villages along the Lhúchir seldom held more than two hundred inhabitants. However, there were many such villages and camps and, in times of need or great danger, a sizable force at arms could be raised from them. The villagers of the Lhúchir were friendly enough to strangers once it was established they were not Angmareans spying out the land. While the Lumimiehet feared the Witch-king and respected of his power, Angmarrim treaded the banks of the Lhúchir at their own risk. The Lumimiehet could supply food, clothing and supplies to travelers in the region, but wanderers had to possess something the villagers valued before any barter would commence.
The villages were more or less permanent settlements, but could move a few miles up or down the river, depending on weather or hunting conditions. The summer hunting camps on the Herd Tundra were more relaxed and less serious than Ystävä Talven hunters elsewhere. The sheer supply of game lessened the worry of starving in the winter months, and hunters had time to talk and give aid to those in need, sometimes even personally guiding wanderers to their village. The relaxed atmosphere of the camps also allowed for a moderate specialization of labor. Since the hunters did not need their arrows immediately, they could wait for the more skillful fletchers to make them. As payment, they hunted on behalf of the fletchers. The camps came and went with the herds, and travelers could not expect to find a camp in the same place twice. They were rough and rustic, and their inhabitants could offer little more than food, shelter and guidance towards other villages along the Lhúchir.
In the 1st Edition of MERP and on Pete Fenlons maps of Angmar and the Grey Mountains this river is named "Lókosir", an erroneous Quenya form.The name was corrected into more adequate Sindarin "Lhúchir" with the 2nd Edition and the release of the "Northern Waste " Sourcebook.