The trail maps for Shenandoah National Park that many folks agree are the most detailed and most accurate are produced by the Potomac Appalachian Trail Club (PATC). This is the same club that takes care of most of the trails in SNP, plus backcountry huts and cabins–so they know as well as anyone the updates to maps and other publications that should occur.
While true that there have only been minor changes to the AT through SNP in the past decade, there have been more significant changes regarding side trails, boundary entrance opportunities, and backcountry rules which are included on the maps. There is one map each for the south, central, and north districts which make them a lot better than other maps which try to cram all that info onto a single map.
Want to do some side trail loops that connect with the AT? Need to get out of the Park fast, especially off-season? This kind of info is essential.
PATC maps are printed in relatively small quantities, and are often updated as necessary whenever a new press run is ordered. Best bet is to order directly from PATC (www.patc.net) or from ATC. Many other retailers sell them, but sometimes they still have old stock to get rid of before they order new versions.
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