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If you don't know what triangulation is, read this article.
The only place you're likely to find a big red "YOU ARE HERE" sign on a mall map, so before you can make use of a topographic map, it must be oriented properly to your surroundings. Knowing which direction North is isn't enough--you must also find your own position on the map
That act of figuring out where you are in relation to a map is called triangulation, a long-winded term for using at least two recognizable landmarks to pinpoint your own position. To triangulate properly you will need a compass, a ruler and a pencil or pen.
Before you leave the house, prepare your map.
Find the declination diagram at the bottom of your map.
It's not necessary to draw lines across the entire map ~ just do the sections you're actually going to use.
In the field, identify at least two landmarks that you see and locate them on the map.
Look for easily identifiable features such as peaks, clearings, lakes, ponds, roads, rivers and buildings. Scan the map carefully until you find two (preferably three) such distant landmarks.
The second landmark should be at a right angle to the first as you look at them in the field; the third should fall between these two.
Mark these landmarks on your map if necessary so you don't "lose" them.
Align your map to your surroundings.
Spread the map out flat.
Triangulate your position.
Repeat steps 1-6 above under Align Your Map To A Landmark.
Your approximate location will be where the 2 lines cross.
To further verify your location, select a third landmark between the first two and repeat steps 1-6. This third line should pass through the intersection of the first two lines to confirm your position. If not, recheck your work for all three landmarks.
I see a stream on my map. How do I find it in the real world?
You may encounter a situation where you can see a choice location on a map, but because the terrain around you blocks the view (high trees, rolling hills, riverbeds and so on), you can't see it in "real life."
After you oriented yourself to the map, you can easily judge the location of a landmark in the field even if you can't see it.
Mark both your current location and destination.
Lay one side edge of the compass baseplate on the map, aligned with these two points. (The direction of travel arrow should be pointing toward the goal, not away from it.)
Holding the baseplate steady on this line, turn the dial until the needle and the orienting arrow line up.
Read the bearing at the marker line.
Pick up the compass and map with the needle still aligned with the orienting arrow, follow the direction of travel line with your eyes. It is now pointing to the object you wish to find in the field.
Getting from here to there, however, probably won't be a simple matter of walking in a straight line. To learn how to navigate around obstacles without losing your way.
I see a peak up ahead. How do I find it on the map?
If you know your position on a map, you can use a compass to identify landmarks in the field.
Let's say you're on a mountain peak, and you'd love to identify a nearby summit so you can brag to your friends back home about the view. Nothing to it!
How do I navigate around this huge bramble patch without getting lost?
Following a compass bearing is hard enough, but nature makes it even more difficult by throwing up obstacles that block your nice straight line. Marshes, ponds, boulders, trees, cliffs, steep slopes, brambles and dense foliage can all thwart hikers trying to follow a straight course. Sometimes, you'll soon find, the shortest distance is not the easiest.
Planning your route in advance helps here. If you know ahead of time, for example, that an outcropping of rock lies between your campsite and that cave entrance, study your topographic map and plot a route around it.
But you never know when your path will be unexpectedly blocked ~ by a fallen tree, a washed out bridge, an unmapped quarry ~ forcing you to navigate around without benefit of planning. Here's how.
The key to making this technique work is keeping out and back portions of the detour equal in length. Keep close track of the number of paces you walk, and keep your strides as uniform as possible.
How do I measure hiking distance accurately on a map?
"Linear distance" and "travel distance" are almost never the same in the backcountry. "As the crow flies," in other words, "ain't as the hiker walks."
If you're trying to estimate how many miles you have ahead of you, measuring the distance straight from point A to point B won't do you any good ~ because unless you're actually a crow, the route you take will likely follow a more roundabout path.
To measure actual or nonlinear distance on a topographic map--of a winding trail, say, or a meandering creek ~ use one of these two methods. (Note that the Paper Method does not work very well on the trail.)
Note: If you're using string or something that won't keep its shape, always keep it anchored with one finger as you move forward. Otherwise, if the string slips you'll have to start over again. Also, don't stretch the string when you straighten it out.
Some guidebook maps will have a numerical scale ~ such as "one inch equals one mile" ~ indicated in the legend, but no accompanying bar scale. In a case such as this, measure the distance with a ruler (there's a small one on the baseplate of your compass) and multiply that number by the scale. A distance of 3.75 inches on a map with a "one-inch-equals-one-mile" scale would represent 3.75 miles on the ground.
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