Statement of Significance (as of designation - February 18, 1997):
An essential step in making large scenic reservations accessible to the motoring public without unduly marring landscape scenery or natural systems was the initiation of "landscape engineering." When it was begun, Going-to-the-Sun Road was the most ambitious road construction project ever undertaken by the Bureau of Public Roads and the NPS. The extreme terrain and conditions, as well as the newness of the administrative agreement between the two federal bureaus, made the road a laboratory of innovative road engineering practices and policies. While building the road, the NPS and the Bureau of Public Roads developed the construction standards and the cooperative administration that characterized future road construction not only in national parks, but on other federal lands and, after 1933, in state parks as well.

Condition:
Since the construction of Going-to-the-Sun Road, traffic volume, avalanches, rock fall, harsh weather conditions, and inadequate maintenance have contributed to deterioration of the structural and historic features of the road. Studies since 1984 have evaluated in detail the condition of the road and priorities for repair. These condition assessments indicate that the road and its structures will continue to deteriorate unless corrective action is taken. If corrective actions are not taken, historic structures will be lost and adjacent environmental resources may be adversely affected.

The FHA/NPS rehabilitation work on Going-to-the-Sun Road is on-going. Phase VI will rehabilitate approximately 3.5 miles of road and stone structures beginning at the West Tunnel. As reported in 2004, the Department of the Interior, National Park Service prepared a Record of Decision on the “Final Environmental Impact Statement for the Rehabilitation of the Going-to-the-Sun Road” (December 2003). The selected alternative will have a significant long-term beneficial effect on cultural resources. The National Historic Landmark designation will be maintained by implementation of rehabilitation measures to repair and protect retaining walls, guard walls, arches, bridges, culverts, and other historic features before further significant deterioration occurs. Under the selected alternative, rehabilitation of the road will be completed over 7 to 8 years, if required funding is available. This alternative accomplishes road repairs while maintaining significant historic features, visitor use, and access.