Page:America's Highways 1776–1976.djvu/509

 View of the completed gallery No. 4 with reinforced concrete lining from across Pine Creek Canyon.

the new district direct supervision of all the work contemplated or underway in the East. The territory of the region included 30 States east of the Rocky Mountains and the District of Columbia. The work in the western States and Alaska remained as organized in 1921 under a Western Regional Office.

All of the park work was performed under the interagency agreement of 1926, and by 1939, 1,577 miles of road in or leading to 43 national parks and monuments had been improved on the national park system. For example, much of the original Yellowstone Park loop road was reconstructed suitable for automobile traffic. The Red Lodge-Cook City approach road to Yellowstone National Park and the Cameron Desert View approach road to Grand Canyon National Park in Arizona were both completed. The Crater Lake National Park loop road in Oregon, portions of the Fall River Highway in the Rocky Mountain National Park, and the Wawona Tunnel project in Yosemite National Park in California were also completed. This tunnel was approximately 4,200 feet in length. The Big Oak Flat Road on which the Wawona Tunnel is located replaced a carriage road built in 1874 which was very narrow with a steep descent into Yosemite Valley. Building a road to acceptable standards to replace the old road called for the best highway engineering skills. The new road, 10 miles in length, included three tunnels, three major bridges, and 2 miles of exceptionally difficult construction. Work was also in progress on the Tioga Pass Road, giving access to Yosemite National Park from points east of the Sierra Nevada Mountains.

Late in 1930, work was begun on the Skyline Drive to provide employment for the inhabitants of the drought-stricken Shenandoah Valley and to open a road in the newly authorized Shenandoah National Park for recreational use.

Today, Skyline Drive extends from the northern boundary of the Shenandoah National Park at the outskirts of Front Royal, Virginia, and then in a southerly direction along the crest of the Blue Ridge Mountains to Jarman’s Gap near where U.S. Route 250 crosses the summit of the Blue Ridge Mountains at Rockfish Gap, a distance of approximately 97 miles. In altitude, the Skyline Drive varies from approximately 600 feet at Front Royal to a maximum elevation on the north section of 3,390 feet on the side of Hogback Mountain. 503