The art of reading a map is slowly going the way of the buffalo as GPS units become more and more available. Smart phones, cars, and standard handheld GPS units are all replacing maps at an alarming rate. While using GPS to get where you’re going is great when you have power, what happens in an emergency when there’s no power to operate the GPS units, or worse yet, if something were to happen to the GPS system itself?
Being able to navigate using a compass and map is not only a good skill to have, it could easily save your life in an emergency. While other people wander aimlessly you’ll be able to get a bearing and get yourself to safety.
Reading and using a map and compass isn’t all that difficult, and with some basic instruction you should be well on your way.
Basic Parts of a Compass
Let’s start with the basic parts of a compass. For someone who hasn’t held one before, the standard compass can seem a little daunting to understand. There are more parts to an advanced compass than listed below, but these are the essentials. You can get a great compass for less than $20 that doesn’t have a sighting mirror, and one with a mirror can run you $80 or more.
- The Index – The Index is a small mark at the top of the compass. This is where you align the degree marks in the dial to to get your bearing.
- The Needle Housing – The needle housing is the part of the compass that the magnetized needle resides in. This, along with the dial, can rotate freely to align the compass with magnetic north and your map.
- Magnetized Needle – The needle in the compass is the part that always points towards magnetic north.
- Dial – The dial rotates with the needle housing to allow you to align the compass correctly.
- Sighting Mirror – Not all compasses come with a sighting mirror, as they aren’t required for you to navigate; they’re just handy to have.
This video from REI shows the basic parts of a compass, too.
Now that you have a rough idea what the basic parts of a compass are, let’s look at the basic parts of a map.
Basic Parts of a Map
When talking about maps and navigation, it’s worth noting that maps that you find in guide books and tourist materials are rarely good enough to use for proper navigation. To navigate a bearing correctly you should use a topographic map so you’re aware of rises and falls in elevation. Without this you could possibly plan a route that takes you up the side of a mountain or into a canyon.
Click the map above for a larger view, click here for the unedited map.
- North Arrow – The north arrow can look different depending on the map you’re using but the basic idea stays the same. The north arrow arrow points to north on the map. This is what tells you where north is on the map so you can align your compass to it.
- Scale – If a map doesn’t have a scale on it, the map is basically worthless. The scale is what tells you how far an inch on the map is in the real world. Measure the distance with the side of your compass and multiply it by the scale to get your distance.
- Elevation Lines – These are what tell you what the elevation is of the various parts of the map. On a good topo map, every 5th line is an index line and should list the number of elevation. These are easy to spot because they’re usually bold. Areas that have steeper terrain will have smaller lines between the index lines, while flatter terrain will only show the index lines.
- Terrain Features – Topographical maps will show basic terrain features like bodies of water, vegetation, rocks, and peaks. Check out the image below to see what these look like.
Here’s another REI video that shows you the basics of a topographical map.
Now that you know what a map’s features are, it’s time to learn how to get a bearing using your map and compass.
Getting a Bearing
The most important thing about plotting a course on a map is knowing where you currently are on the map. Without this important piece of information it becomes nearly impossible to plot a proper course. There are ways to figure out where you are on a map using a compass, but that’s another topic entirely. For now, we’ll assume you know where on the map you are.
Once you know where you are, place a dot on the map to signify your starting point. Next, determine where on the map your destination is and place a second dot. Using the flat edge of the compass, draw a line between each point. With your compass aligned to this line, turn the dial until the north arrow printed inside the housing lines up perfectly with north on the map. The magnetic needle will almost always not be perfectly aligned with the map’s north, which is why the dial of the compass rotates.
At this point you should have the following:
- Starting point drawn on map
- End point drawn on map
- Line drawn between both points
- Compass dial rotated so the printed north arrow in the compass aligns to the map’s north arrow.
Once the dial’s north arrow matches the map’s arrow, look at what degree mark is lined up with the index mark on the compass. This is your bearing. In the example below, the bearing is 20 degrees.
Your bearing is the degree off of north that you’re heading paired with the general direction, so above would be northwest, 20 degrees.
Ok, so you know the basics of your compass and map, and you have a bearing. The last big question is what do you do with that bearing?
Navigate Using a Bearing
Once you have your bearing from the compass it’s time to get walking. Holding the compass out in front of you so you can see the dial, rotate the compass body until the magnetic needle lines up with the printed arrow inside the compass housing. Once these line up, your path of travel will be towards the index mark on the compass.
The index point will be your direction of travel. The magnetic needle and printed arrow are only there so you know what direction you’re traveling in, not so you walk towards them.
Once you get the direction you need to travel in you may think that you should keep the compass in front of you the entire time so you don’t get off course. This is a very bad idea for a number of reasons, most importantly the fact that while you’re paying attention to your compass, you’re not noticing the world around you, which can be VERY dangerous.
Instead of looking at your compass the entire time, look at where the compass is aiming you and pick something out as far off in the distance as possible and use it as a navigation milestone. This is where a compass with a sighting mirror comes in very handy. Hold the compass at eye level, like the picture below. Then, use the index mark as a sort of gun sight to pick out a landmark to be your temporary destination.
Once you choose something far off in the distance to walk towards, take a few steps to either side and find the landmark again. Make sure it’s engrained in your brain so you can always find it again. If it’s a tree, pick out something specific about it so you can distinguish it from the other trees.
Now that you have a landmark to move towards, put the compass away. You can start walking towards your landmark and if something like a stream or other obstacle gets in your way and makes you detour, you can always just find that landmark again and head towards it. Once you reach the landmark pull out the compass and choose a new landmark to walk towards. Continue the process until you get to where you’re going.
Wrap-Up
Learning how to navigate by using a compass isn’t difficult and after you do it a few times you should be pretty good at it. Take the time to practice this skill now so when you’re in a survival situation it’s just like second nature to you instead of yet something else you have to learn on the fly to survive.
