How to Use a Compass to Safely NavigatePublished on 12/28/2021 · 9 min readA compass is an essential item for your wilderness safety, but do you know how to use one? Camping & Hiking Expert Elle Matthews shares everything you need to know.
Photo by Ali Kazal
Navigators relied on the sun and stars to find their way until a tiny magnet that always points north opened up new avenues in exploration. A compass, still to this day, is considered to be the most reliable tool for navigation—technology can only take us so far. GPS systems are only as good as it’s battery life. The sun changes with the seasons and sometimes you’re caught under a cloudy sky.
A compass can get you out of a sticky situation anywhere, and in any kind of weather, only by the hands of its user though. Here and now is the best time to learn about a compass and the value of knowing how to use it. It’s part of the 10 essential items to bring on any hike. Don’t let your ego run wild; getting lost in the wilderness happens to the best of us.
A clear foundation with straight edges and a ruler to measure distance on a map.
Direction-of-Travel Arrow/Direction Arrow
Point this arrow in the direction you want to go.
To help see the fine details of a map.
This marker helps pinpoint your marked bearing.
Needle Housing/Compass Housing
The main part of your compass that contains liquid and a magnetic needle.
Moves with the bezel. When the magnetic needle and the orienting arrow come together this is known as putting “red in the shed.”
When orienting a compass to a map, align these with the vertical grid lines.
A small magnet with a red end that always points towards Earth’s magnetic north.
An adjustable indicator that you can “set and forget” to an area's magnetic declination.
Rotating Bezel/Azimuth Ring
Marked with 360 degrees, rotate this to find your bearings.
More Compass Jargon
The 4 main points of direction; north at 0/360 degrees, east at 90 degrees, south at 180 degrees, and west at 270 degrees.
Points of direction that are halfway in between cardinal points, northeast, southeast, northwest, and southwest.
Secondary Cardinal Points
Compass points that are halfway between a cardinal point and an intercardinal point; North-Northeast, East-Northeast, West-Southwest, South-Southwest, etc.
Types of Compasses
If you’re shopping for your first compass, I highly recommend going with a baseplate. You don’t have to spend more than you’d like, but because it’s so popular at any experience level, it has a wide price range.
The primary qualities you want in a compass are a baseplate, a magnetized needle, a rotating bezel, cardinal directions, and degree markings. Some other convenient features include an adjustable declination, a sighting mirror, and luminescent bezel and markings. A compass comes in all shapes and sizes, but these are 3 common choices for hiking.
A classic choice among hikers and backpackers. They are straightforward and easy to use. Practice your navigating skills with one of these before you grab a compass with all the bells and whistles. Mirrored baseplate compasses add a layer of protection to the housing.
Also known as the military compass, these can be a bit daunting. They are known for top-notch accuracy and durability. This compass is best for experienced navigators and extreme, rugged adventures.
These little gadgets are commonly used in orienteering. It fits on the thumb so that you can align the compass to the map in one hand. This compass is best for activities like trail running when you want to quickly and easily navigate.
The Care and Keeping of a Compass
- Don't store a compass in direct heat.
- Avoid being rough and reckless with a compass.
- Don’t store a compass close to batteries, electronics, or metal.
- Make sure the compass needle moves smoothly and settles on north within around 3 seconds.
- Keep your compass clean. The bezel should move easily but not be too sticky or too loose. When dirt gets stuck in the bezel, it causes disruptions to the rotation.
A cracked compass housing could lead to leaks, and if you notice bubbles in the liquid, then you definitely have one and it’s time to get a new compass. However, bubbles arise even without a crack. This could be from high-pressure areas, pressure changes, and cold temperatures. As long as these bubbles remain relatively small, it won’t interfere with the movement of the compass needle and is still safe to use. Magnets and metals with a lot of iron, known as ferrous metals, could damage the magnetic needle’s accuracy. Be cautious about where you store a compass. Avoid prolonged contact around cell phones, car keys, car speakers, radios, etc.
Adjust for Declination
A map and compass point at two different north poles. Before any adventure, the first thing you need to do every time is to adjust your compass for declination to avoid traveling off course.
The geographic northernmost point where all lines of longitude meet is true north. You could think of it as the same North Pole where Santa will come from to drop off your new compass this year. Earth has a magnetic field with its own defined north and south poles. A compass arrow points to the magnetic North Pole, whereas a map points in the direction of true north.
Magnetic declination is the angle of difference between true north and magnetic north.
Over time, the magnetic poles will move, causing the angle of declination to change. So it’s important to make sure your map and declination value are up to date. Find an area’s current declination using NOAA’s magnetic field calculator, or printed in the bottom margin of a topographic map like the examples in the pictures.
How to set the adjustable declination varies per compass. Some have a key that you insert in the back which allows you to move the bezel. When declination points east, subtract that value on your compass dial from 360 degrees. If declination points west, add that value to 0 degrees.
If your compass doesn’t have an adjustable declination then make sure when you use your compass to do the math and add or subtract the number of degrees from the direction you want to go.
To figure out the length of your journey, use the written scale and bar scale at the bottom of your topographic map. These scales represent map distance in relation to ground distance. In the example above, the map’s written scale is 1:24,000—meaning 1 inch on the map equals 24,000 inches in real life. Inches will always be used for a topographic map’s written scale ratio just as there will always be 12 inches in a foot and 5,280 feet in a mile. The bar scale provides a visual reference with measurements already converted to feet, miles, or kilometers. Use a shoelace or some type of string as a little trick to increase accuracy and include the turns and switchbacks.
Understand the Terrain
Shenandoah's Hiking Difficulty is a formula used to calculate trail difficulty according to distance and elevation gain.
Use the contour lines on a topographic map to learn the shape and elevation change of an area. Every fifth contour line is referred to as the index line—it's bolder than the rest and written somewhere along that line is the exact elevation. For more on using topographic maps, check out my article How to Read a Topographic Map!
The closer these lines are to each other, the steeper the climb or fall, and vice versa, where the further apart, the more gradual the incline or decline.
Orient a Map
To orient a map means to rotate it to match the terrain. Doing this makes it easier to understand your current surroundings when looking at a map. 1. Lay a map out on a flat surface. 2. Set declination according to your location. 3. Make sure the north on your compass is at the index line. 4. Put the compass on the map so that the edges are straight with the north/south grid markings. 5. Without moving the compass from its position, rotate the map until the magnetic needle fits the orienting arrow. 6. With “red in the shed” or “dog in the doghouse,” the north on your map is now in the same direction as the north on your compass.
Take a Bearing
Now you are ready to take a bearing—or find the direction of travel in degrees! 1. Draw a straight line from your current location (point A) to your desired destination (point B). 2. Take the edge of the compass and connect point A to point B. 3. Make sure the north on your map and the compass needle stay pointed in the same direction. 4. Turn the rotating bezel on your compass until red is in the shed again with the compass needle fitting the orienting arrow. 5. The degree indicated by the index line tells you what direction you need to go in order to reach your destination.
Use Triangulation If You Get Lost
STOP: Stop, Think, Observe, and Plan.
Stay calm, try to recall some details about your surroundings up to this point. Then look around and pick out a landmark. If necessary, hike up to an area where you can get a good eye on geological features. 1. Point the direction-of-travel arrow towards a specific landmark and adjust your compass so that red is in the shed. 2. Look at the index line and that degree is your bearing. 3. Orient your map. 4. Lay your compass down with its orienteering lines matching the eastings on the map, keeping red in the shed, and the edge of your baseplate lined up to the chosen landmark. 5. You are located somewhere along that line of your baseplate. 6. Draw that bearing line. 7. Repeat these steps with a different geological feature. 8. You are standing at the point where the two lines intersect.
Know Before You Go
It’s simple to bring a compass and map on your hike but the most important part is being able to use them and having the education on how to use your tools. Hiking is easy to do with nothing but your own two feet. However, Search and Rescue reports day hikers as the ones most often found in a survival scenario. Continue using these practices in all your endeavors and they will soon become second nature.
If you have any questions or need help picking out a compass of your own, reach out to a Camping & Hiking Expert here on Curated!