Secretary of the Interior Stewart L. Udall and First Lady of the United States Lady Bird Johnson at Grand Teton National Park in 1964. Udall was a strong supporter of the Appalachian Trail and helped with the passage of the National Trails System Act of 1968 that created the Appalachian Trail as a national park.

In 1978, Congress amended the National Trails System Act to substantially increase the pace of land acquisition along the trail corridor. The Act appropriated $90 million in new funds for this purpose and led to the acquisition of private lands along more than 800 miles of the Trail.

The Act also instructed the Secretary of the Interior, in consultation with the Appalachian Trail Conference, to submit "a comprehensive plan for the management, acquisition, development, and use of the Appalachian Trail." This plan was to include the "identification of all significant natural, historical, and cultural resources to be preserved." One consequence of this provision in the Act was the rerouting of the existing trail to new locations, such as McAfee Knob, that were deemed "significant" and worthy of preservation.