During the first four decades of the Trail's existence, the majority of its route passed over private property. The local trail clubs and the ATC secured rights of way over these private lands through a series of agreements--some formal, some informal--that gave the clubs the right to build the trail across an individual's land, gave hikers the right to pass through, and sometimes included the right to build a shelter on the landowner's property. This sample easement from 1938 shows that the ATC was often able to secure these rights of way at minimal cost (in this case, $1.00). At the same time, these agreements were very fragile, generally giving the landowner the right to revoke or cancel the agreement with 30 days notice. As a result, the Trail was often rerouted when an easement was canceled, or when the property through which it passed changed hands.

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.