A data book is a collection of largely useless facts and numbers, fascinating to those stomping around in the middle of nowhere, or, for the less adventurous, one of the places right next to nowhere.
Those who happen to be doing that very thing because they want to. And are curious to have facts with them. On their way from one arbitrary line on a map to some other arbitrary whatever. For some reason. Or other.
To them, these stompers, these gritty shufflers, these backpackers, these thru-hikers, to them all facts are useful. Even facts detailing the locations and peculiarities of resupply stops and where said stops used to be. Unless they are no longer, any more, because the place silently dried up and the wind caught it by one corner and and blew it off the map on a dry, overcast, empty dead Thursday.
Even facts, getting back to facts, that state mileage between any two random, boring points on the trail ... are important ... to backpackers ... who have ... nothing ... else to, uh ... think about.
How cool is that then? How? Think.
Even facts. More facts. About how. Steep. The trail gets. And where exactly that happens. That happens. Steep. And where shelters and camp sites are. Road crossings. Water sources. Various facilities. Various. And major features. Features. Major ones.
Major features, whatever major features are, like those stores that sell only gasoline, whiskey, and moth balls? And ammo? Some of them? But apparently remain relevant to long distance hikers who need something to think about, to keep them from going nuts and gnawing off a leg. Even more nuts. Which would make it tough to keep walking. Though more interesting, in a way, due to the challenge though.
Which is another fact, if you will. Which is why data books were invented, to carry around facts. And are still popular among the challenged. Thru-hikers. Challenged in many ways, they.
Like the data book for the Appalachian Trail, a data book published for over 25 years now, and one or more for the Pacific Crest Trail, and so on and so on, for trails all over. The place. Of which there are oh, so many. So many. Trails and places that need facts to be put into books and carried. Another fact.
Go figure, etc.
Source: how to talk in the woods.