The idea for an Appalachian Trail was conceived by forester Benton MacKaye in 1921. In 1925, the Appalachian Trail Conference, a private not-for-profit organization, was founded specifically to coordinate the development of the Appalachian Trail. Its mission today is to preserve, manage, and promote the Appalachian Trail. By 1937, an Appalachian Trail footpath was considered complete and open for all to enjoy. In 1968, Congress passed the National Scenic Trails Act that created a system of national scenic trails, starting with the Appalachian Trail and Pacific Crest Trail.
Though considered part of the national park system, the Appalachian Trail has largely remained managed by the Appalachian Trail Conference. This responsibility was formally delegated by the Department of the Interior in 1984. Today, the trail and its associated lands are managed by the Appalachian Trail Conference, its 31 affiliated trail clubs, and the National Park Service Appalachian Trail Park Office, in conjunction with several agency partners including the USDA Forest Service and numerous state park and state forest agencies.
All digitized information used to create this data set were based on information depicted on USGS 1:24,000 topographic maps or Appalachian Trail maps, which vary in scale from 1:24,000 to 1:100,000. Generally, this information was only used as a supplement to the GPS data (e.g. in areas where no GPS data was collected or where GPS data did not reflect current conditions such as recent relocations). Though no formal tests were conducted, those portions of the data based on USGS topographic map information are assumed to be within National Mapping Standards. Those based on Appalachian Trail map information, however, may exceed National Mapping Standards in some areas. All portions of the data based on digitized information are noted within the attribute information.
All GPS data was post-process differentially corrected either by A.T. staff members or by the party that collected the data. Next, it was populated with data source and supplier information. All GPS data used to create this data set was collected using Trimble's recommended data capture settings (e.g. maximum PDOP of 6.0 and elevation mask of 15 degrees) except the Manual 3D setting for those data collected by Dr. Vernier. Dr. Vernier used the Automatic data setting, which collects 3D GPS data when available and 2D GPS data all other times. Those portions of the data based on 3D GPS data and those based on 2D GPS data were identified and noted in the data. All GPS data were then combine to produce a seamlessly data set and attribute information (e.g. length) was updated for the entire set.
Gaps were then identified and supplemented using digital data based on information depicted on USGS 1:24,000 scale topographic maps and Appalachian Trail maps, which vary in scale from 1:24,000 to 1:100,000. Attribute information (e.g. length) was then updated for the entire set.
Data were then compared to a list of major trail relocations since 1998. Those portions of the data set that no longer accurately depicted the current trail location (e.g. the trail had been relocated since the GPS data in that area was collected) were replaced with digitized information, based on the most accurate and up-to-date information available as to the current trail location, whether that be an Appalachian Trail map (1:24,000 to 1:100,000 scale) or marked up USGS topographic maps (1:24,000 scale). Once combine with the rest of the data set, attribute information (e.g. length and data source) were updated for the entire set.
As more accurate and up-to-date information is collected or becomes available, it will be incorporated within, or used to update, the current data set.