Land Navigation: How to Orient With a Map & Compass

It’s not as easy to get lost on land without a map and compass. The keys to successfully navigating the wilderness are being able to determine your position, know where you’re going and understand how terrain affects your movement abilities.

The “how to orient a map using a compass” is a skill that can be used in the outdoors. The skill allows users to find north with ease, which is crucial for navigation.

Welcome back to the Land Navigation Manual for the Art of Manliness. We covered how to use a compass correctly, how to shoot your bearings, and the greatest map for navigating: the topo map, in Part I. We still need to understand where we are in reference to our map — how to orient ourselves — before we can start really navigating, which we’ll cover in Part III of this series. So in this episode, we’ll go through the abilities you’ll need.

Declination Adjusting Your Compass

Remember how we spoke about declination in Part 1? We need to compensate for the compass now that we’ve placed it on the map so that we can appropriately orient and travel.

Before we do that, let’s take a closer look at declination. It will be clearer why we need to compensate for declination in the first place.

True north and magnetic north are not the same, as stated in Part I. Magnetic north is now off the coast of Greenland, but true north is at the very top of the world. Declination is the angle formed by true north and magnetic north. But here’s the catch: depending on where you are on the planet, the angle of declination varies.

Take a look at the map below:

Isogonic lines show magnetic declination.

Have you noticed the “agonic line”? Magnetic north lines up exactly when you’re on this line and facing true north. There is no declination, and you do not need to adjust your compass.

However, imagine you’re in Muir Woods in San Francisco, facing true north. Magnetic north would be around 14 degrees to your right, or east. When you point your compass towards true north, the needle will point slightly east. It’s declination is recorded as 14E.

Let’s go to the other side of the country. Assume you’re in the Adirondack Mountains of New York. When you face true north, magnetic north is roughly 14 degrees to the left, or west, of you. When you point your compass towards true north, the needle will point a bit to the west. As a result, its declination would be 14 degrees west.

Basically, the compass needle will point someplace east of true north in locations west of the agonic line, whereas it will point somewhere west of true north in areas east of the agonic line.

What happens if you don’t compensate for declination with your compass? Let’s return to Muir Woods as an example. If we don’t account for declination and use our map to acquire directions to our destination, we’ll be wrong by 14° or more when we start walking. That has the potential to make a significant impact!

To prevent this issue, we’ll tweak our compass to account for declination.

Magnetic declination land navigating.

1. Check the declination of your local location on your map or on a website. This webpage may also be used to get current declinations. As you can see, the declination of the location I’m in is 4E.

 

Taking magnetic declination into account on compass.

2. Turn your compass on its side. Isn’t that a little black arrow outline? We’ll adjust it to account for the declination of our compass.

Declination marks on compass.

3. Because my magnetic declination is 4E, I’ll move the black arrow outline to the red hash marks next to “E DECL.”

Magnetic Compass.

4. Using a little screwdriver or the metal piece that came with your compass’ lanyard, turn the small screw. You’ll want to rotate it till the black arrow outline matches the 4E hash mark.

Compass adjusted for magnetic declination.

5. The big bang. Declination was taken into account while adjusting the compass.

What if you don’t have access to a compass that can compensate for declination? To make sure you receive a correct bearing, you’ll have to perform some arithmetic with all of your bearings.

If your local declination is east of the agonic line, you’ll need to add the declination to your compass bearing; if it’s west of the agonic line, you’ll need to remove the declination from your compass bearing.

So, if you’re at Muir Woods and your compass reads 180 degrees, subtract 14 degrees. As a result, your real bearing is 166°.

If you’re in the Adirondacks, add 14 degrees to get a correct bearing of 194 degrees.

When your compass can’t adjust for declination, you may make your own declination arrow out of masking tape and attach it below your compass under the right declination degree hash (This will only work if your compass has a clear base). Instead of using your compass’s arrow, you’ll align your needle with the tape arrow.

Getting Your Map Oriented to True North

We’re ready to start orienting ourselves now that our compass has been corrected for local declination. The first step in orienting ourselves with our map and compass is to double-check that north on the map corresponds to north in our landscape. Keep in mind that maps are drawn with north at the top. Everything on your map will be reversed if you’re looking south and holding the map right side up.

Fortunately, orienting your map is simple.

Orienting with map and compass.

On your map, place your compass. Look at the red needle to see which direction it is pointing.

Orient map 2.

Turn your map so that north on the map corresponds to the needle’s orientation.

Using a Map to Get a Direction

Assume you’re going on a short trek from one location to another. You can’t shoot a bearing on the end point in your terrain since you can’t see it. On your map, though, you can see the two spots. To obtain a heading from our map, we may use our compass as a protractor. We may then use our compass to begin going in the direction we need to go in order to reach our destination.

This is how you do it:

Taking a bearing with map and compass.

1. Center the compass on the map, with one of the baseplate’s long edges running between the two places of interest. Make sure the travel direction arrow is pointed in the direction you want to go. (Note: The magnetic compass needle should be ignored.) Throughout this procedure, we’re not utilizing it at all.)

 

Taking a bearing with map and compass.

2. Adjust the compass bezel so that north on the compass corresponds to north on the map. Housing lines should be parallel to the vertical grid lines on the map.

Taking a bearing with map and compass close up photo.

3. Look at the index line and read the number. From point A to point B, that’s your bearing.

Using Your Compass to Transfer a Bearing to Your Map

1. Using your compass, take a heading to a visible landmark.

2. Determine your position on the map and set the compass edge over it.

3. Rotate the compass until the north on the bezel points to the top of the map and the compass housing orienting lines are parallel to the map’s vertical grid lines, using your position as a pivot. The compass baseplate’s edge is now pointed in the direction of the visible landmark you used to get your bearing.

Using Point, Line, and Area Position to Determine Your Location on a Map

Let’s pretend you’re on a hike. You’ve got your dependable compass and a map of the region, but you’re not sure where you are in respect to the map. You can figure this out with a little compass work.

Position of the point. You have your “point location” when you know precisely where you are in reference to your map.

We may use the map to identify any landmark we observe in our landscape once we know our point location. Assume you’ve climbed to the top of Camel’s Hump in Vermont. You notice another mountain peak out in the distance, but you don’t know what it’s called. All you have to do now is take a bearing towards the unnamed mountain. You learn that it has a 176° bearing. Using the approach described above, plot that bearing on the map.

Mt Ethan Allen topo topographic map.

Mt. Ethan Allan, the peak you observed, is cut through by the plotted line. Huzzah!

When we don’t know where our point is, we have to rely on less precise kinds of orientation based on line or area position:

Position of the line. When you have a line location, you know you’re on a map’s recognizable line (trail, ridge line, etc. ), but you’re not sure where. You are missing your point location. It’s not an issue. To figure out precisely where you are on the map, you simply need one more piece of information.

Topographic topo map with roads mountains.

We’re headed to the Wichita Mountains Wildlife Refuge in Oklahoma for this example. We know we’re someplace south of Saddle Mountain on HW 115. We just don’t know where we are. However, we should be able to figure it out rather quickly.

At the summit of Saddle Mountain, take a bearing using your compass. You can see that the mountain is 24 degrees away from you.

Compass 1.

Navigate to your map. Make sure your map is aligned with magnetic north (see above). Shoot the reverse bearing you got with your compass from the top of Saddle Mountain on your map. It would be 204° (24+180) in this situation.

 

Draw a line towards the roadway you’re on using the side of your compass. On the map, you are where the line connects with the highway.

Position in the area. What if you’re not on a route and just have a broad idea of where you are? So, how are you going to acquire your point position?

Easy.

Unknown area on a map.

Assume you’re southeast of Saddle Mountain and northeast of a few of lesser peaks.

To begin, use your compass to locate a peak on Saddle Mountain. It’s 310 degrees in reference to you, as you can see. We’ll use the rear bearing of it to draw a line on the map from Saddle Mountain to our approximate direction. That’s 130 degrees.

Draw a line on the map at 130 degrees from Saddle Mountain. You’re on that line, so you know where you’re standing. We’re going to figure out where we are on that line now.

Area plot on a map.

Take a compass bearing on the peak to your southwest. It’s 230 degrees in reference to your position, as you can see. The rear bearing is at a 50-degree angle. Plot a line on the map using the mountain’s rear bearing. More or less, where the second line meets the first is where you are on the map.

So there you have it. The fundamentals of using a map and compass to find your way around. Next month, we’ll wrap off our series with a final briefing on how to navigate using MGRS coordinates, exactly like the military.

So there you have it. The fundamentals of using a map and compass to find your way around. Next month, we’ll wrap off our series with a final briefing on how to navigate using MGRS coordinates, exactly like the military.

Additional Reading and Resources

FM 3-25.26: Map Reading and Land Navigation

Navigation in the Wilderness

The Ultimate Guide to Navigation

 

 

The “orient a map to the ground by map-terrain association” is one of the most basic skills that you will need in order to survive. It is easy to learn and it can be done with just a map and compass.

Frequently Asked Questions

How do you orient and read a map?

A: In order to orient and read a map, you have to have spatial awareness.
Looking at the map is an easy way of finding which direction north or east are relative to your current position. Spatial awareness refers to having knowledge about where everything in the environment is located relative as well as understanding how objects relate with each other spatially.

How do you orient a map to ground?

A: You can use the arrow keys, or you can hold down shift and move in any direction to rotate a map around its axis.

How do you do map orientation?

A: To rotate a map in Beat Saber, you can hit the trigger button on your controller. Youll see that it shows two arrows when you turn your headset or controllers around to show the new orientation of a map.

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