Designed to connect the Shenandoah National Park in Virginia and the Great Smokey Mountains National Park in North Carolina, the Blue Ridge Parkway was planned to provide pleasant motoring and to conserve and interpret the unique natural and cultural resources of the Southern Highlands. It was conceived also as a public works project to relieve unemployment in the Appalachian region during the Great Depression.
Depression

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Image Credit: Courtesy Flickr/thewebprincess (CC BY-ND 2.0) Image Caption: A stunning view from an outlook on the Blue Ridge Parkway, which is famous for its beautyEra_date_from: 1935
1999

The Bonneville Dam, Columbia River Power and Navigation System consists of 55 major projects on Oregon's Columbia River and is said to be the largest hydroelectric system in the world.
The Columbia River forms part of the border between Washington and Oregon and flows inland through the only waterway that crosses the Cascade Mountains. To harness the energy of the ninth longest river in North America, engineers developed unique design and construction approaches to overcome problems caused by depth of water, current velocity, and an irregularly-shaped river bottom.
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Image Credit: Courtesy Flickr/Ann Larie Valentine (CC BY-SA 2.0)Image Caption: The impressive power of the Bonneville DamEra_date_from: 1938
1987