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The fall line has meanings in both geographical features and the sport of alpine skiing.
Geographical fall line As a geographical feature, the fall line marks the area where an upland region (continental bedrock) and a coastal plain (coastal alluvia) meet. The fall line is typically prominent where a river crosses it, for there will usually be rapids or waterfalls. Because of these features river boats typically cannot travel any farther inland. Because of the need for a port and a ready supply of water power, settlements often develop where the river crosses the fall line. Fall lines in the United States Along the eastern coast of the United States, the east-facing escarpment where the Piedmont of the Appalachian Rise descends steeply to the coastal plain forms a fall line over 1500 kilometers long. The fall line is a zone that may be several km wide. Geologically the fall line marks the boundary of hard metamorphosed terrane—the product of the Taconic orogeny—and the sandy, relatively flat outwash plain of the upper continental shelf, formed of unconsolidated Cretaceous and Tertiary sediments. In the 19th Century, the fall line often represented the head of navigation on rivers at points like Little Falls, on the Potomac River. However, since the advent of flumes for water supply and canals for shipping in the early 20th Century, the most prominent feature of fall line settlement was the establishment of the cities along it. As the cities were linked by the early highways, U.S. Route 1 and Interstate 95 came to pass through many of these cities, roughly tracing the fall line. Cities along the fall line include, from north to south: See also Alpine skiing fall line In alpine skiing, a fall line refers to the line down a mountain or hill which is most directly downwards. This can be visualized as the route a ball would take if it were started rolling at the summit, and rolled to the bottom. | ||||||||
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