The Loup River is a tributary of the Platte River, approximately 68 miles long, in central Nebraska in the United States. The river drains a sparsely populated rural agricultural area on the eastern edge of the Great Plains southeast of the Sandhills. The name of the river means "wolf" in French, named by early French trappers after the Skidi band of the Pawnee, …The Loup River is a tributary of the Platte River, approximately 68 miles long, in central Nebraska in the United States. The river drains a sparsely populated rural agricultural area on the eastern edge of the Great Plains southeast of the Sandhills. The name of the river means "wolf" in French, named by early French trappers after the Skidi band of the Pawnee, whose name means "Wolf People," and who lived along its banks. The river and its tributaries, including the North Loup, Middle Loup, and South Loup, are known colloquially as "the Loups", comprising over 1800 mi of streams and draining approximately one-fifth of Nebraska.