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Posted by Bill S on April 3, 2008 at 1:19:14 pm EDT
In reply to National Geographic Topo Question posted by BigSky on April 2, 2008 at 9:39:13 am EDT

turneej -
Learn to read terrain first, then learn to read topographic maps (what do all those multi-colored lines mean, anyway - blue, brown, black, green patches, ...), and then learn to relate the map and terrain to each other. The best way to do this is get topo maps of the area you are in or going to (NW Alabama has some interesting terrain that will include most of the important types of features) and get out there with the map in hand. Let me emphasize - MAP IN HAND!!! not tucked away in your pack. Keep following on the map continuously where you are. Follow trails at first (being line features, it is fairly easy to track your location - follow the turns in the trail, and note surrounding features - branch streams, hills, etc). And keep the map oriented as the ground lies (too many people hold the map with the north edge "up", rather than matching the ground). Find some high places and sit for an hour or two at each matching the map and terrain.

There are a number of good books that will lead you through the basics, although there are organizations that do hiking and orienteering that will teach you. Look at the land navigation books from The Mountaineers Press, National Outdoor Leadership Schools (NOLS), etc (you can search on Amazon).

Orienteering is an excellent and fun way to learn matching map to terrain. Look on the US Orienteering Federation website http://www.us.orienteering.org/. There is an orienteering club in Alabama - Vulcan Orienteering Club (VOC) - c/o James Pilman, 2875 Blackjack Rd., Trussville, AL 35173. 205-437-0550 (Ka4zqa at aol.com). Their website is http://home.earthlink.net/~ciza/voc.html. They will be glad to teach you all about map and compass, and for free (except for the entry fee to their events, which basically pays for the map). They have upcoming meets at Oak Mountain State Park, just south of Birmingham, on Apr 19 and May 17.

After you learn to match map and terrain, then learn how to use the compass (actually pretty simple, but too many people teaching compass complicate it with magic formulas about declination, where in fact there are simple, intuitively obvious ways of dealing with that). Frankly, in all the years I have been wandering the woods, hills, deserts, tundra, and "frozen wastes" on 6 continents, I have rarely used a compass except for rough orientation of the map (and there are very few places in the world where you need to worry about the magnetic declination for that). As I have posted here before, I have only gotten lost once in my life, at age 5, wandering around Tegucigalpa by myself. And yes, I do know how to use a compass, surveyor's transit, sextant, various radio-navigation devices, and GPS (I worked for about 10 years on various aspects and applications of the Global Positioning System) - wonderful devices all, but only as aids to navigation, not substitutes for knowledge and experience.

After you have gotten comfortable with map and compass, then, and only then, should you even consider getting into coordinate systems. Coordinate systems are really unnecessary for 99% of what the backpacker or hiker does. As I said in my previous post, coordinate systems are just an address system. It really does not matter which system you use (and eventually you will need to be familiar with both UTM and lat-lon). Whether you use lat-lon or UTM (MGRS or one of the country-specific variants), you just measure E-W and N-S. Some maps are cluttered up with a UTM grid overprint, which does sometimes make UTM coordinates more convenient (note that I did NOT say "easier"). If you use a computer program like NatGeo's Topo!, you can get the coordinates by pointing to the desired location and either reading off the position or clicking to mark a waypoint to download to your GPSR - no need to measure (you can also load the map to a PDA and do the same thing). For a paper map (which I recommend you should always carry), you can print the map with either a lat-lon grid or a UTM grid. I don't really recommend this, since it just adds more clutter to the map.

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