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Learn to use a map and compass


Master the art of navigation and you’ll never get lost again. In our seven-part backcountry navigation course on Outside Learn, you’ll learn everything you need to navigate on and off the trail, from using GPS and digital maps to orientation on the trail. old with a paper map and a compass. Join the class now and learn at your own pace.

Of course, not everyone who wanders is lost. But when you’ve been going in circles for hours and your day hike turns into a night, this saying is a cruel joke. The solution? Don’t get lost in the first place. Learning to use a map and compass is something all hikers and backpackers should do.

Even experienced backpackers sometimes neglect their navigation skills, but when the trail runs out of steam or is covered in snow, knowing how to chart your own path is absolutely essential. And even in the age of GPS and smartphones, the most reliable way to ensure you stay on track is to pack a map and compass and know how to use them. Below we will cover both the basics and some finer points of compass navigation.

Plus: Don’t get lost with our Backcountry Navigation course on Outside Learn.

Why should I learn to use a compass?

With the advent of GPS, compass navigation has become a lost art. It’s easy to see why: under clear skies, modern GPS receivers can pinpoint a user’s location accurately and quickly with little or no user skill.

But here’s the thing: GPS units are electronic, and the electronics fail at the most inopportune times. Sometimes they run out of battery; sometimes, after years of use, they fail. Also, they can usually only tell which direction you’re facing once you’re on the move.

Compasses, on the other hand, are nearly indestructible. They don’t take batteries, have no screens to break, and don’t need software updates. And when protected by waterproof coatings or careful storage, cards rarely fail. Keeping these two simple items in your bag – and knowing how to use them – is a small step that could save you a lot of trouble.

Tip: Once you’ve mastered old-school navigation, you can use apps like Gaia GPS to check your work or get more specialized data like slope angle.

Magnetic compasses use the earth’s magnetic field. (Photo: Massimo Colombo/Getty Images)

Know Your Compass

A compass is the most reliable method of navigation, but it’s useless if you don’t know your way around. Different types of compasses have different parts, but here are some common components.

Base plate : A transparent back that shows the card underneath. The ruled edge helps with triangulation and landmarking.

Direction arrow: This shows you where to point your compass when taking a bearing.

Index line: An extension of the direction of travel arrow that indicates where to read bearings.

Rotating bezel: A circular area marked with numbered degrees (clockwise) from 0 to 360.

Magnetic needle: Located inside the bezel, it always points to magnetic north, not true north. (They are hundreds of miles apart.)

Orientation arrow: This helps align the scope with the directions on the map.

Declination scale: Hash marks inside the bezel designed to help adjust declination. (Not sure how to do this? Read on.)

Declination correction

One of the tricky parts of navigating with a compass is that magnetic north is not the same as true north. The angle between the two, known as declination, varies depending on your location. It also changes gradually over time as the Earth’s tectonic plates shift. If you don’t adjust your compass to compensate, you’ll end up in the wrong direction.

The easiest way to find the angle of declination is to check your map: most have declination charts, as well as the date of the last revision. Since declination changes over time, newer maps will have more accurate numbers. There should be an angle and a direction, for example, 8 degrees East.

Are you working from an old map? Check online. There are several different services that can use where you will be hiking to calculate your declination.

Once you have your declination, subtract it from your compass bearing for west and add it for east. If you have trouble remembering this rule, try this mnemonic device: Maps Tell Almost Everything (Magnetic to True: Add East).

Fun fact: Compasses first appeared in China around 200 BC. AD and were probably used for divination. The declination was not discovered until around 720 AD.

lensatic compass
Lensatic compasses are accurate but have a learning curve. (Photo: Adamantios)

What are the different types of compasses?

While there are many types of compasses on the market, the most common for backpackers is the baseplate compass, which consists of a liquid-filled compass face attached to a flat, clear piece of plastic. Besides being cheap and simple, a baseplate compass, with its transparent design, is easy to use with a map.

Lensatic compasses are also popular, which open like a medallion and use a sighting wire in the cover and a rear lens to take very accurate bearings. Although they have the advantage of being accurate and durable, lensatic compasses have a slightly steeper learning curve.

Because baseplate compasses are the most widely used, our instructions here will focus on them. If you have a lensatic compass, your steps may vary slightly. Metal interferes with the magnetic needles of compasses, so avoid spreading your map on the hood of a car.

Want to triangulate your location? Start by identifying a few landmarks. (Photo: Ken Conger/NPS)

How to find your location with a compass

Pinpointing your location with a map and compass is easy if you know how. First, you will need to be able to find at least two known landmarks. (Mountains and lakes are good choices.) If you can find a third, even better. As always, don’t forget to adjust the declination.

1. Using your compass, orient your map so that north points to true north. (Pro tip: Make sure the fixed grid lines on your compass line up with the north-south grid lines on your map.)

2. Take a bearing to your first landmark: line up your direction of travel arrow with your landmark, then rotate the scope until the needle lines up with the north marker. (The number next to the index line is your bearing – more to come.)

3. On the map, place one corner of your compass ruler over the landmark, then rotate the compass assembly until the needle lines up with north on the bezel. Using a pencil, draw a line along the edge.

4. Repeat steps 2 and 3 for your other marks. The point where all the lines intersect is your approximate location.

How to find your bearings with a compass

If you already know your location, you can use your compass to determine how to get to any point on your map. After adjusting your compass for declination, start by orienting your map to true north, as in the instructions above.

1. Place the corner of your compass base plate on your position, then rotate your entire compass until the ruler forms a line between your position and your destination.

2. Rotate the scope until the grid lines on the base plate match the grid lines on the map.

3. Read the number next to the index line—this is your bearing.

4. Holding the compass level in front of you, turn your body until the north arrow on the bezel matches the compass needle. Your direction of travel arrow should now point to your destination.

Use your smartphone as a compass

Your smartphone can do everything else, so it’s no surprise that it has a built-in compass. With the right app (try Digital Field Compass for Android, or for a more comprehensive experience, Gaia GPS for iPhone and Android), you can use your phone as a navigation device, no GPS required.

Apps use your phone’s magnetometer. After a simple calibration process, it can not only do everything a compass can do, but can even lock onto a bearing well enough to tell you when you’ve strayed.

Of course, phone-based compasses come with some important caveats. Biggest: Just like your phone’s GPS, all of these apps require a charged battery to run. That’s why we recommend everyone to learn how to use a normal analog compass. You can count on him to keep working no matter what you put him through. Once you’ve fully developed these skills, you can use your phone’s GPS without worrying about running out of juice.

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