Courtesy of   G u y   M o t t GPS and Google Earth Data for the Appalachian Trail
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Home Adventure Tree Website Info GPS and Google Earth Data For The Appalachian Trail Adventures	2008-11-29 Update Notice Elevations have been added to all track points and waypoints. Additionally the data values have been rounded slightly. For more information see the update description at the bottom of this page. General Information From this page you can download GPS files and Google Earth files for the Appalachian Trail. I've climbed New Hampshire's 4000 footers, hiked the 500 mile Colorado Trail, and some friends are hiking the AT in 2008 and I will be joining them for a week so I got interested in GPS data for the AT. In the end, after a lot of work, I generated track and shelter data for the entire AT that I think is pretty useful so I'm sharing it with whomever is interested. If you're interested in how these data got generated then see the Data Genesis section at the bottom of the page. Most, I'm sure, will simply want the data so they're directly below. Please note this important information: These data were obtained from the Appalachian Trail Conservancy website and are a translated and modified representation of the AT Conservancy data. There are limitations on the use of these data as specified by the Appalachian Trail Conservancy, including but not limited to "These data are not considered an official source of information for navigation" and there is "no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data". Please see the AT Conservancy's download agreement concerning these data. (Note: if above link does not work then please go to the AT Conservancy homepage, search for "GPS", click on the "Appalachian Trail GIS and GPS Data" link, then click on the "Data Download Agreement" link). Since I have not improved these data in any way except to translate them to the WGS84 reference datum, with the inevitable loss in positional accuracy that results from any translation process, I make no representation beyond the AT Conservancy's statement for the usefulness of these data. Also note that the original data were posted in 2002 and some parts of the trail and some shelters may be different today. Data Description There are 39 tracks that run consecutively from Georgia to Maine. Additionally there are tracks 35_1 and 35_2 (in file 35_1.gpx) that are short spurs to the top of Mt. Washington in New Hampshire. Most full-resolution tracks have approximately 10,000 points and some have fewer, to a minimum of about 2,000 points. Tracks come in these varieties: Full Resolution = Unfiltered; contains the maximum number of points at intervals from 1 foot to 0.4 mi (over 2000 feet). The total number of points for the entire AT is about 312,000. Filtered 50 Feet = Filtered to space points at approximately 50 feet or more. The total number of points for the entire AT is about 134,000. Filtered 200 Feet = Filtered to space points at approximately 200 feet or more. The total number of points for the entire AT is about 46,000. Filtered 10,000 Points = Filtered to create a track with 10,000 points or less. A track this size loads into the Garmin MapSource program within a reasonable time. Filtered 500 Points = Filtered to create a track with 500 points or less. This is the maximum size track that may be loaded into a representative GPS unit (Garmin 60CSx). Note that filtering for a specific interval (e.g., 50 feet) does not reduce the gap between widely spaced points in the original, unfiltered data. Wide gaps in the original data remain in the filtered data. E.g., a 2000 foot gap remains a 2000 foot gap. Shelter data consists of waypoints for 290 shelters along or near the AT. Each waypoint contains a comment with info about the shelter. Long comments contain complete information from the original AT Conservancy data. Note that shelter capacity=0 indicates that it is unknown. Short comments are 30 characters or less and may be loaded without truncation into a GPS unit (at least into my Garmin 60CSx). Short comments say (1) what type of shelter, (2) capacity, (3) if camping is allowed, and (4) if there is a fee. Also the shelter names may or may not include a leading 3 digit number, which is the consecutive number of the shelter from South to North. Shelters are named as follows: For waypoints that contain long comments, the name may be the original name, e.g., "Whitley Gap Shelter". Or it may be the original name with a leading 3 digit number delimited by a space, e.g. "008 Whitley Gap Shelter". For waypoints that contain short comments, the name may be the original name sans spaces, e.g., "WhitleyGapShelter". Or it may be the same format name with a leading 3 digit number, e.g., "008WhitleyGapShelter". (Note that "501Shelter" is changed to "154The501Shelter") Track files either do or do not include shelter waypoints. Shelter waypoints are not included unless it is specifically indicated that they are. Shelter waypoints in all files have long comments except in files with 500 point tracks, in which shelter waypoints have short comments because, presumably, you'll be using this data directly in a GPS unit. All location data is WGS84 reference datum. I have NAD27 data for some things but it is limited utility in GPS units and cannot be used in Google Earth so I'm not currently making that data available. GPS data downloadable from this website is contained in .gpx files, which is a standard format for interchange of GPS data. Sometimes the .gpx files are augmented by .gdb files containing identical information (see info about Garmin MapSource below). Google Earth data is contained in .kml files. Garmin MapSource is a free program that may be downloaded from the Garmin website. Even without a Garmin GPS unit, this is a useful program for working with .gpx files (edit and filter tracks, edit and create waypoints and routes, etc.). While MapSource works well with .gpx files, it natively uses .gdb files, which save and load quickly. A good trick is to open multiple instances of the MapSource program (i.e., multiple windows). Then you can load different collections of tracks and waypoints into different windows and you can copy and paste between windows to compose any mixed collection of tracks and waypoints that you want. Google Earth has the capability to load .gpx files allowing you to display tracks and waypoints. Use the [ File | Open ...] menu choice then, in the [ Files of type: ] list box, select [ Gps (*.gpx *,loc) ]. Don't try to use the [ Tools | GPS ] menu item unless you want to buy a subscription to Google Earth Plus. Data Downloads These files are zipped for download efficiency. Shelters Appalachian Trail Shelters, GPS and Google Earth (92 KB) = 4 GPS files and 1 Google Earth file for the 290 Appalachian Trail shelters. 2 .gpx files have long comments with 1 file having original names and the other consecutive names. The other 2 .gpx files have short comments with 1 file having non-consecutive names and the other consecutive names. The .kml file has original names and long comments. Tracks Appalachian Trail GPS Tracks, Full Resolution (3228 KB) = 39 .gpx files, each with a single track, plus "35_1.gpx" with 2 spur tracks to top of Mt. Washington. Altogether these tracks cover the entire Appalachian Trail. These tracks contain the maximum number of points, sometimes very close to each other. Appalachian Trail GPS Tracks, Filtered 50 Feet (1505 KB) = 39 .gpx files, each with a single track, plus "35_1.gpx" with 2 spur tracks to top of Mt. Washington. Altogether these tracks cover the entire Appalachian Trail. Points are approximately 50 feet or more apart. Appalachian Trail GPS Tracks, Filtered 200 Feet (575 KB) = 39 .gpx files, each with a single track, plus "35_1.gpx" with 2 spur tracks to top of Mt. Washington. Altogether these tracks cover the entire Appalachian Trail. Points are approximately 200 feet or more apart. Appalachian Trail GPS Track Collection, Full Resolution (6200 KB) = A single file containing all tracks from the "Appalachian Trail GPS Tracks, Full Resolution" files above. A .gdb file that contains identical information is also supplied. Appalachian Trail GPS Track Collection, Filtered 50 Feet (2835 KB) = A single file containing all tracks from the "Appalachian Trail GPS Tracks, Filtered 50 Feet" files above. A .gdb file that contains identical information is also supplied. Appalachian Trail GPS Track Collection, Filtered 200 Feet (1043 KB) = A single file containing all tracks from the "Appalachian Trail GPS Tracks, Filtered 200 Feet" files above. A .gdb file that contains identical information is also supplied. Appalachian Trail Single GPS Track, Full Resolution (6189 KB) = A single track containing the maximum number of points, sometimes very close to each other, for the entire AT. A .gdb file that contains identical information is also supplied. The huge track in the .gpx takes a very long time to load in MapSource. Appalachian Trail Single GPS Track, Filtered 50 Feet (2835 KB) = A single track containing points spaced approximately 50 feet or more apart for the entire AT. A .gdb file that contains identical information is also supplied. The very large track in the .gpx takes a long time to load in MapSource. Appalachian Trail Single GPS Track, Filtered 200 Feet (1034 KB) = A single track containing points spaced approximately 200 feet or more apart for the entire AT. A .gdb file that contains identical information is also supplied. The large track in the .gpx takes a while to load in MapSource. Tracks with Shelters Appalachian Trail GPS Track Collection with Shelters, Full Resolution (6261 KB) = A single file the same as "Appalachian Trail GPS Track Collection, Full Resolution" above plus all shelters including long comments. A .gdb file that contains identical information is also supplied. Appalachian Trail GPS Track Collection with Shelters, Filtered 50 Feet (2895 KB) = A single file the same as "Appalachian Trail GPS Track Collection, Filtered 50 Feet" above plus all shelters including long comments. A .gdb file that contains identical information is also supplied. Appalachian Trail GPS Track Collection with Shelters, Filtered 200 Feet (1103 KB) = A single file the same as "Appalachian Trail GPS Track Collection, Filtered 200 Feet" above plus all shelters including long comments. A .gdb file that contains identical information is also supplied. Appalachian Trail Single GPS Track with Shelters, Full Resolution (6250 KB) = A single file the same as "Appalachian Trail Single GPS Track, Full Resolution" above plus all shelters including long comments. A .gdb file that contains identical information is also supplied. Appalachian Trail Single GPS Track with Shelters, Filtered 50 Feet (2884 KB) = A single file the same as "Appalachian Trail Single GPS Track, Filtered 50 Feet" above plus all shelters including long comments. A .gdb file that contains identical information is also supplied. Appalachian Trail Single GPS Track with Shelters, Filtered 200 Feet (1095 KB) = A single file the same as "Appalachian Trail Single GPS Track, Filtered 200 Feet" above plus all shelters including long comments. A .gdb file that contains identical information is also supplied. Miscellaneous Collections - I live in New England and I hike New Hampshire's White Mountains so many of these collections are for those regions. Miscellaneous Appalachian Trail GPS Track Collections, Filtered 50 Feet (3874 KB) = Each file has a collection of tracks that are filtered to space points approximatly 50 feet or more apart. 2 versions of each file are supplied either containing or not containing shelter waypoints, which include long comments. Includes files for the southern half of the AT, the northern half of the AT, New England and New Hampshire. Miscellaneous Appalachian Trail GPS Track Collections, Filtered 200 Feet (426 KB) = Each file has a collection of tracks that are filtered to space points approximatly 200 feet or more apart. 2 versions of each file are supplied either containing or not containing shelter waypoints, which include long comments. Includes files for New England and New Hampshire. Miscellaneous Appalachian Trail GPS Tracks, Filtered 50 Feet (2369 KB) = Each file has a single track that is filtered to space points approximately 50 feet or more apart. 2 versions of each file are supplied either containing or not containing shelter waypoints, which include long comments. Includes files for New England, Massachusetts, Vermont, New Hampshire and Maine. Additional .gdb file is supplied for New England. Miscellaneous Appalachian Trail GPS Tracks, Filtered 10,000 Points (462 KB) = Each file has a single track that is filtered to 10,000 points or less and loads reasonably quickly into MapSource while retaining good resolution. 2 versions of each file are supplied either containing or not containing shelter waypoints, which include long comments. Includes files for the full AT and New England. Miscellaneous Appalachian Trail GPS Tracks, Filtered 500 Points (103 KB) = Each file has a single track that is filtered to 500 points or less and thus may be used directly in a GPS unit. 2 versions of each file are supplied either containing or not containing shelter waypoints, which include short comments. Includes files for the full AT, New England, Massachusetts, Vermont, New Hampshire and Maine. Google Earth Files Appalachian Trail Google Earth Track Collection, Full Resolution (4050 KB) = A single file containing multiple tracks with the maximum number of points, sometimes very close to each other, for the entire AT. 2 versions of the file are supplied either containing or not containing shelter placemarks, which have long comments. Appalachian Trail Google Earth Track Collection, Filtered 50 Feet (1906 KB) = A single file containing multiple tracks that are filtered to space points approximately 50 feet or more apart for the entire AT. 2 versions of the file are supplied either containing or not containing shelter placemarks, which have long comments. Appalachian Trail Google Earth Track Collection, Filtered 200 Feet (731 KB) = A single file containing multiple tracks that are filtered to space points approximately 200 feet or more apart for the entire AT. 2 versions of the file are supplied either containing or not containing shelter placemarks, which have long comments. Datum Comparison, Google Earth (242 KB) = Comparison of track and shelter locations in the original NAD27 reference datum and corrected WGS84 datum locations. See the properties for the "Appalachian Trail Datum Comparison" folder for more information. In addition to showing the error in using NAD27 in previously distributed files, this is a pretty good general illustration of the difference between NAD27 and WGS84 reference datums. Data Genesis This topic on the Google Earth Community Bulletin Board was the start for generating these data. Note that my posts are from user QuiGonJin. Originally the data came from the AT Conservancy website, GIS and GPS Data webpage. (Note, if above link doesn't work then go to the AT Conservancy homepage, search for "GPS", then click on the "Appalachian Trail GIS and GPS Data" link). Somebody in the Google Earth Community translated the ESRI data from the AT Conservancy into a Google Earth file "888578-AppalachianTrailCenterline.kmz". It was great to be able to trace the entire length of the AT in Google Earth. Unfortunately there were a couple of problems: The original data uses the NAD27 reference datum whereas Google Earth requires the WGS84 datum and GPS units natively use WGS84 datum. Using the wrong datum causes a location error that can be off by many hundreds of feet. The ESRI data consists of over 4500 small tracks in arbitrary order and direction, thus the data was virtually unusable (outside of ArcMap) for anything except gazing at the track of the AT. Had I known what lay ahead I probably would have gone no further. But I thought I could write a small program to link those 4500+ tracks together and generate usable GPS data. Unfortunately, the linking process produced many errors and strange pairings, due mostly to loops and clouds of closely spaced points that probably resulted from GPS "fix wander" while stationary, and also because the ESRI data apparently did not allow lines to cross each other therefore lines were split where they crossed. It took a lot of effort to fix up these problems and generate contiguous tracks but I was able to accomplish it resulting in 39 ordered tracks from Georgia to Maine for the entire Appalachian Trail. Along the way I noticed that the original data had not been translated into WGS84 so I used NADCON to accomplish that. Note that NAD83 is virtually identical to WGS84. I also found online some GPS waypoint data for shelters along the Appalachian Trail that, like the tracks, had been ported from AT Conservancy data. As I began to integrate this shelter data with the tracks I discovered, unfortunately, that The locations had not been translated from NAD27 to WGS84. Much of the auxilliary information (e.g., shelter capacity, description, etc.) was missing or truncated and thus unusable. I went back to square-one with the shelter data, translating the AT Conservancy's AT_Shelters_mif data to WGS84 and composing the information for each shelter into usable waypoint comments. After all that, the track and shelter data is now accurate for WGS84 and quite usable and forms the basis for composing various collections of tracks and waypoints as presented above. Update (20081129): In addition to all the above, elevations have been added to all track points and waypoints. This elevation data was generated by Chris Johnson and generously donated by him for inclusion in the files on this site. This is a great addition to these data and I, as I'm sure all users of this data, really appreciate it. Take a look at Chris's website where he has lots of cool maps and elevation profiles, including a collection of elevation profiles for the Appalachian Trail. Also in this update all lat / lon points are rounded to 6 decimal places and elevations are rounded to 2 decimal places (meters). These provide resolutions to within ~6 in for location and ~0.4 in for elevation, which is well within the accuracy of the data. Better efficiency is achieved by limiting the decimal places to reasonable resolutions.