Reddit mentions of Pisgah Ranger District [Pisgah National Forest] (National Geographic Trails Illustrated Map (780))

You use one of these (download the TIFF file) and a compass. There are better ones out there (this is a really good one of the same location), but the USGS map does the job just fine. See the Wikipedia page on topo maps. It allows you to determine location (by finding the direction of multiple known locations, like radio antennas, buildings, or mountains, and tracing them back to their intersection) and terrain (how steep inclines are, water, elevation, the easiest routes, etc), in addition to the usual roads, buildings, etc.

Topo maps are a ton of fun to use, especially if you have to figure out exactly where you are (perhaps this could be implemented in a game by only displaying the correct quadrangle (or an equivalent) and it requires you to figure it out for yourself. I really want to play an ES game with a mod that does this now, I might have to start learning how to do it (and figuring out how to make the required maps).

The 3D map (I haven't seen it in use) sounds like it's just a more user-friendly (though less directly informative) way of doing the same thing as a topo map. Topo maps are fun, and not too difficult to learn, but few people know how to read them, and fewer know how to use them properly; to be fair, it's no longer a required skill given the pervasiveness of GPS and turn-by-turn directions (which I have no problem using), but it's invaluable if you ever need it, and helpful even when you don't.

This is from national geographic trail map http://www.amazon.com/Pisgah-District-National-Geographic-Illustrated/dp/1566953324

Any outdoor recreation shops will have all the maps you need: REI, Diamond Brand, Frugal Backpacker, a lot of the bike stores, etc. This is the best map you can get for finding trails, planning routes, etc. Although it's not the most detailed map as far as Topography goes, find one of the more specific USFS maps for this.

http://smile.amazon.com/Pisgah-District-National-Geographic-Illustrated/dp/1566953324/ref=sr_1_1?ie=UTF8&qid=1457370678&sr=8-1&keywords=natgeo+pisgah+map