There is an area in eastern Nebraska where the Platte River, after flowing northeastwardly from the vicinity of Kearney for nearly 150 miles, enters the glacial drift bordering the Missouri Valley and turns directly east. Over its eastward course of about 50 miles, the river forms a shallow and wide sandy channel that is bounded to the south by forested bluffs and to the north by a wide wooded floodplain. One of these glacially shaped and loess-capped bluffs was known historically to the resident Pawnee tribe as Pahaku (usually but incorrectly spelled as Pahuk) Hill. This Pawnee word may be roughly translated as "mound on or over water," or "headland." The bluff is one of five natural sites (four of them along the Platte River) in the historic range of the Pawnees that were considered sacred to them, and it is the only remaining location that is still virtually biologically intact. About 50,000 years ago, during late postglacial times, this bluff also marked the approximate point where the Platte River abruptly turned southeast. It then followed a glacial moraine valley, now known as the Todd Valley, toward present-day Ashland. Although this part of the lower Platte Valley is now recognized for its uncommonly rich bottomland soils, it is also rich in Pawnee history, since the Platte and Loup Valleys were among the most important parts of the Pawnee's original homeland.
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