Written by 4:12 pm Wilderness Navigation Masters

25) Techniques to locate yourself on your map

Reading Time: 10 minutes(Last Updated On: June 7, 2021)

Hello and welcome to this lesson of the online course Wilderness Navigation Masters, where you will learn how to locate yourself on your map.

In this lesson, you will learn:

 In the first scenario, you will learn how to locate yourself, using two landmarks.

  • In the second scenario, you will learn how to locate yourself on a linear landmark, like a river, using only one landmark.

These 2 techniques are known by the name of triangulation.

  • In the third scenario, you will learn how to locate yourself on a linear landmark without any other landmark.
  • After all of this, we will finish with two advanced techniques, that can help to locate yourself on your map, with the help of only one point-landmark, identified both on your map and around you.

So, first thing first, how to locate your position on your map using a minimum of two identified landmarks :

Before I show you how, I want you to know that you should not take the result of your location as 100% exact, because it’s just an approximative result.

 

How to locate yourself using only two landmarks:

Now that you understand this point, let’s see how can you apply the first technique:

[Skip video to 1:04]

SHOW TRANSCRIPT
  • Step 1: Adjust your compass for declination, by marking it on the back of your compass if you have a baseplate compass like mine, or insert the little key in the hole and turn it, if you have one like this.

  • Step 2: In order to take a back bearing of your identified landmark, aim at it with the direction-of-travel arrow and turn the housing till the south of the magnetic needle sits in the orienting arrow.

  • If you have a baseplate compass like mine and you have your declination marked on the back, the south of the magnetic needle should sit in this new mark.
  • If you have the other compass type, with the little key and are adjusted for declination, or you have a negligible declination, the south of the magnetic needle should sit in the orienting arrow.

 

  • Step 3: read the back bearing value at the intersection between the dial with graduations and the direction-of-travel arrow.

Now, in order to plot (draw) the back bearing on your map, you should align the edge of your compass with this identified landmark, making sure that the direction of the travel arrow point to your approximate location on your map and not the opposite.

This is why you should always keep knowing where you are approximately on your map.

Then, turn all of your compass and not only the housing, till the top of the orienting lines are up and parallel to one of your geographic north-south lines.

Draw a line that goes from your identified landmark.

Repeat this with another landmark, preferably another two, to have a total of three used landmarks.

The final result will be something like that … three lines that intersect, and your position are in the middle of this triangle.

 

One thing that I want you to know before I move to the next scene. In order to get a useable result, your landmarks should not be close to each other by an angle below 50°, or too much away from each other by an angle of more than 140°.

Because, if you do that, you will get something like that.

And just a minor error when you were taking or plotting your bearings on your map, will have a big impact on your approximate location.

Now let’s move to see how can we locate ourselves approximately on our map, being on a linear landmark and having only one identified landmark.

 

How to locate yourself on a linear landmark with one identified landmark only :

Useful when:

Knowing how to locate yourself on your map, with the help of another landmark is useful when you are on an existing linear landmark, like a trail or next to a river, or on an imaginary linear landmark, like between two-point landmarks and you want to pinpoint where you are along with this linear landmark.

Before I show you how I want you to know that this is possible with only one identified landmark, but you can use another one to be more accurate.

[Skip video to 4:33]

SHOW TRANSCRIPT

Let’s say that we are hiking following the Homestead Hill Trail, and we want to know, are we here, here, or here? Because we want to know the remaining time to arrive at this trail’s intersection.

What I can see around me are these two mountains. And from my topographic map, I know that this is Lion’s head, and this is Pierson Mountain.

I can locate myself with just one landmark, but because I want my result to be more accurate I will use these two landmarks.

When I aim at the Pierson Mountain with my compass, I get a back bearing of 90°, and when I do the same thing with the Lion Head mountain, I get a back bearing of 165°.

When I plot these two back-bearings on my map, I know that my position is in this trail, between these two points.

Locate yourself along with a linear landmark :

If you are following a trail or you are next to a river or a creek.

Even when you can’t identify any landmark on your map, you can still locate yourself in this linear landmark.

This is possible due to the bearing differences along with this linear landmark. Because this bearing is different from this one, this one, and this one.

Let’s say that you are hiking following this trail, and what you can see is this.

Walk till you get a long enough section of this trail in the front of you, and measure the direct bearing of this section of the trail, after you adjust for your declination of course.

Let’s say that what you found is a direct bearing of 240°.

Put your compass on your map with the orienting lines up and aligned with one of your geographic north-south lines, and keep moving your compass without turning it following your trail, till the direction-of-travel arrow are parallel to a long enough section of your trail on your map.

You are along this part of your trail.

This is the least accurate technique in this lesson.

Because, when you try to take the bearing of this long enough section in the front of you, you can still rotate your compass with an angle of 5° and this new bearing still represent this long enough section at the front of you.

So, apply this technique with some flexibility. And pay attention to the other sections of your trail that have approximately the same bearing.

For example, the bearing of this part is similar to this one.

So, what you can do is to walk a little bit and analyze the topography around you.

If you get a little turn to your right, you are nowhere, and you were here before.

And if you didn’t get any considerable turn for the approximate time to travel this distance, you are in this part of the trail.

That’s all for this technique that is frequently used in the wilderness to locate yourself, now let’s see the last two techniques that are advanced.

 

Advanced techniques to locate yourself:

These last two techniques are just a geometry magic trick that you can apply in order to locate yourself in the wilderness.

The first one is the isosceles triangle technique.

Isosceles triangle technique :

[Skip video to 8:06]

SHOW TRANSCRIPT

This technique is based on the fact that … if we walk in this line of the isosceles triangle, and we stop here …. because we know that these two sides of the triangle have exactly the same length, if you’ve walked, let’s say 1 km in this way, you are away from this landmark by 1 km in this bearing.

The problem now is, how can you know that you’ve walked to this isosceles triangle sides intersection point? Because, if you walk in the exact same line but in a short distance, you will not have an isosceles triangle.

Or, if you’ve walked the exact same distance, but in a different direction, you will not have an isosceles triangle.

So, let’s see how to walk, to form the sides of an isosceles triangle.

Step 1: Take the foreward bearing to the landmark.

Step 2: Choose a bearing that is between 20° and 80° bigger than this bearing.

For example, if this bearing was 10°, you are free to walk following bearings between 30° and 90° to get a useable result.

Step 3: Let’s say you chose to walk following a bearing of 70°. Note the angle between the first bearing and the second one. In this case, it’s an angle of 60°, because 70° – 10° = 60°.

Note that.

Step 4: Start walking in this direction, following your desired bearing, and count your traveled distance.

If it’s short, you can use the pace counting technique. If it’s long-distance, you can use walking speed.

Now, in order to stop exactly at this isosceles triangle sides intersection point, you should stop at the point where this angle equals the double of this angle.

If this angle was 60°, we should stop at the point where this angle equals 120°.

The foreward bearing to the landmark of this point that we should stop at equals, the value of the second bearing minus this angle.

In this case, it equals 310°. Because, 70° – 120° = -50

And in a 360 degrees circle, -50 is the angle of 310°.

Step 5: As you walk, take foreward bearings to your landmark, till you get a foreward bearing of 310° and stop.

Now, you’ve walked in one of the sides of your isosceles triangle. And your traveled distance equals the distance between you and the landmark.

Step 6: To locate yourself on your map, draw this line with the bearing of 310° to the landmark.

If you’ve walked for 0.8 miles the first time, in a topographic map with the scale of 1:25000, 0.8 mile equals 1 inch. So, on your map, you are 1 inch away from your landmark in this line.

As you see, it’s not an easy technique. So, I advise you to watch it more than one time to understand it well.

The most important part of this technique is your ability to measure your traveled distance. The more accurate you are in measuring your traveled distance, the more accurate are your approximate location on your map.

Now that we’ve seen the isosceles triangle technique, let’s see the next advanced technique and the last one in this lesson.

 

2 Back bearings technique :

[Skip video to 12:28]

SHOW TRANSCRIPT

Let’s say that we are somewhere at this line, and we know the back bearings of this two lines and the foreward bearing of our travel line.

If we traveled 2.4 miles, on a topographic map with a scale of 1:25000, this travel distance equals 3 inches on your map.

The 3-inch line in the direction of our walking bearing, that can fit exactly between these two lines are unique and are the one we’ve traveled, and from that, we can know our approximate starting and actual position.

If you did not understand what I’ve just said or why this is true, you have another chance in this step by step how to :

Step 1: Measure the back bearing of your distinguished landmark and plot it (draw it) on your map.

Step 2: Choose a bearing that you can follow walking in a straight line, till the first back bearing change with a minimum of 30°, to get a useable result.

This means, if the first back bearing was 210°, we have to walk in this straight line till the first back bearing is more than 240° or below 180°.

Step 3: While you are walking in this straight line, count your traveled distance, using pace counting technique if it’s a short distance or walking speed if it’s too long.

Step 4: When the first back bearing change with a minimum of 30° stop, and plot it on your map. Let’s say that the second back bearing measure 180°, draw it like that.

Step 5: Plot on your map this foreward bearing that you’ve walked following.

Step 6: On your map scale, convert this traveled distance to map distance on a piece of paper or on your compass string.

Step 7: Parallel to your foreward bearing walking line, slide this piece of paper between these two back bearings lines.

It can fit exactly between these two back bearings lines under these conditions only in one line, and this line is your traveled line.

And from that, this intersection is your starting point, and the other one is your actual location on your map.

Of course, these are just approximate locations.

Because, like in the previous technique, the accuracy of these locations are linked to how accurate you are in taking and plotting the foreward and back bearings and especially how accurate you are in measuring your traveled distance.

Don’t worry if it’s not easy for you to understand these two techniques, because they are really advanced.

And in the wilderness, most of the time, the other first 3 techniques we’ve seen in this lesson are enough to locate yourself.

EXERCISE

Exercise

In this lesson’s exercise :

  • 1 – I want you to go outdoor with a topo map of this area.
  • 2 – Stand next to a distinguishable landmark, to pinpoint your location exactly on your map,
  • 3 – Take the back-bearing of three landmarks on the terrain and plot them on your map. The more these lines intersect next to your location on your map, the more accurate you are on triangulating your location.
  • 4 – Walk following a linear landmark like a trail or next to a river, and locate your location approximately with the help of the back bearing of just one landmark around you, then with the help of the forward bearing to the section at the front of you, as you’ve seen before.
  • 5- Because the last two techniques are less used in the wilderness, and in order to not overwhelm you with too many techniques, I want you to only master them theoretically by rewatching them more than one time.

That’s all for this lesson, I’m sure that you have at least one question in this informations dense lesson. so to put it in the comments section below.

Thank you and see you in the next lesson.

Last modified: June 7, 2021

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