One Dirty Magazine

Map and Compass Navigation Is An Essential Trail-Running Skill

You can't always rely on your phone apps for directions.

Elizabeth Carey January 29th, 2018

Map and Compass Navigation Is An Essential Trail-Running Skill Photo by Jason Hatfield.

A trail buddy and I ran through lush layers of green on Tiger Mountain outside of Seattle, winding through a rainy forest on cushy pine-needle trails. As we labored uphill, rain turned to snow. At first it was enthralling, as it coated ferns like sugar, but soon it began to fall heavier, obscuring the singletrack.

At each trail junction, we checked the route I’d mapped on Strava and printed out with cues, but somewhere we veered off track. We ran-walked back and forth on a stretch of trail, from one unfamiliar junction to another, debating where we were and where we should go. Without cell service, I lacked a blue location circle on Google Maps; in the cold, my friend’s phone battery drained precipitously.

As our hands numbed in the freezing air, twilight fell and our time-on-feet  surpassed our fitness levels, I realized I lacked the navigation skills and tools that any self-respecting trail runner should have.

Luckily, a trail angel appeared around a turn and kindly lead us to the trailhead. The next day, I signed up for a map-and-compass course.

Nowadays, trail runners have a plethora of digital navigation tools literally at their fingertips, via apps like Gaia and Strava, which offer downloadable map and GPS capabilities. But smartphones are often useless in the backcountry: Batteries die, screens break, cell signals fade.

Ladia Albertson-Junkans, winner of the 2017 Chuckanut 50K and the top U.S. finisher at the Trail World Championships, carries a compass and topo maps on long, remote runs. “It’s so easy to miss a turn or get confused, especially if there are a lot of intersecting spur or social trails,” she says.

Here are some basic map and compass skills every trail runner should have.

What is a topo map?

Topographic maps show what simple trail maps lack: geographic features, such as altitude and grade, which are denoted by contour lines that connect all points at a given elevation. Dense (i.e. close-together) contour lines indicate steep terrain; when contour lines are spread out, the terrain is more gradual. Look for concentric rounds to find, say, a mountaintop. Thicker index lines include elevation.

Not all maps show the same level of detail—some show more information about a smaller area, while othes show less information about a greater area. Scale is the ratio of paper-map space to real-life space. Every topo map has a legend, a key to decoding various map symbols, including lines, colors, contour intervals and—this is important—magnetic north. (We’ll come back to that.)

Check public-land websites, a local outdoor store and specialty companies like Green Maps for up-to-date maps.

How to read a topo map.

While looking at the map, picture the terrain as if you were running. Identify landmarks and terrain features that will help you reach your destination. A great example is following a river upstream to a trail junction. Also practice identifying features or distance markers beyond your destination, which signal that you’ve overshot your mark.

While on the trail, keep your eyes peeled. “Know what should be coming up. Look for clues,” says Lisa Jhung, trail runner and author of Trailhead: The Dirt On All Things Trail Running. “It’s a good idea to look over your shoulder at key trail junctions to see what the turn will look like coming back.”

What is a compass?

A compass should include a clear baseplate with a straight-edge ruler along one side, and a 360-degree rotating bezel. It should also have three arrows: a direction of travel arrow (printed on the baseplate), an orienting arrow (printed inside the bezel) and a magnetized arrow that floats around and points north.

But, because of the molten (i.e. moving) consistency of the earth’s core, geographic north—also called “true north,” the point denoted on the top of your map and compass—dffers from magnetic north—the point your compass needle actually swivels to. The difference between true north and magnetic north, called declination, changes based on where you are in the world.

For example, in Seattle, the declination is 20 degrees east—that is, magnetic north is 20 degrees further east than true north. Check National Ocean and Atmospheric Administration’s site to find your local declination. Your compass should include a declination adjustment, which allows you to set your bezel to account for a specific declination.

The compass’ meridian lines (and orienting arrow) line up with the north-south grid lines on the map; the direction of travel arrow is pointing toward a destination (likely the peak in the upper right corner) and the magnetic arrow lines up with the orienting arrow. Photo courtesy Quique251 / Wikimedia commons.

How to use a map and compass to roughly orient yourself

The most basic rule of using a topo map: “Hold it so that it’s facing the right direction,” says Jhung. If you don’t recognize where you are, this can be surprisingly difficult. Here’s how to use your compass to orient your map in the right direction.

  1. With your map on a level plane, put your compass (with the declination set) on top of the map.
  2. Point your direction-of-travel arrow towards the top of the map, and then turn the bezel so the N identifier lines up with the travel arrow.
  3. Line the vertical straight edge of your compass up with either the right or left side of the map.
  4. Slowly rotate yourself in place, holding the map and compass as level as possible, until the magnetized needle lines up with the orienting arrow.
  5. You are now oriented to view the surrounding landcape identically to how it looks on a map, with north directly in front of you.

Get your bearings

If you want to figure out what direction to go to get to your destination, you need to take a bearing—a direction identified in degrees. From north, in a clockwise direction, the compass identifies east (90 degrees), south (180 degrees) and west (270 degrees). If you get turned around, recite “Never Eat Shredded Wheat” while pointing clockwise at each quarter hour to remember which direction is which.

“Learning how to shoot bearings is scientific. But it’s handy,” says Jhung.

There are two ways to find your bearing: on the map or in the field. That is, you can either find a bearing by identifying your destination on paper, or you can find it by identifying your destination in the real world.

 

If you can point to where you are and where you want to go on a map, but can’t see your intended destination in the real world, you can take a map bearing to figure out what direction to run.

  1. Identify both your You-Are-Here spot and your destination on the map.
  2. Line up the straight edge of your compass on the map between those two locations, making sure to orient your travel arrow towards the your destination (not your current location).
  3. Turn the bezel so that the orienting lines are parallel to the map’s north-south grids, and the bezel correlates with north on the map.
  4. At the index line, read the bearing.

Once you’ve found your bearing on the map, it’s time to apply that reading to the field.

  1. Keeping the compass level, point the travel arrow away from you.
  2. Turn in place until the north-facing, magnetized needle aligns with the orienting arrow.
  3. Now follow your travel arrow, which is pointing along the bearing you found with the map.

 

If you can see a destination or landmark in the real world, but don’t know where you are, take a field bearing.

This strategy is helpful for figuring out how far along a route you’ve gone, or identifying prominent but unknown landmarks. Elinor Fish, founder of Run Wild Retreats + Wellness, uses this technique on group runs all over the world. “When it’s a trail I’m not familiar with, I’ll check our progress and orientation as we go, for reassurance and also to tell the group where we are,” says Fish. “The danger with running is you just want to make progress. You don’t want to break stride or momentum. But when you don’t do that, you can get off track.”

To find a field bearing:

  1. Identify a landmark that you can see and also locate on your map.
  2. With your compass level (and declination set), point the travel arrow at the landmark.
  3. Rotate the bezel until the magnetized needle lines up with the orienting arrow.
  4. Look at the index line to read the bearing.

Once you’ve taken a field bearing, transfer that bearing to the map, to either confirm that the landmark you see is the one you think it is or to figure out where you are currently along the trail. (If you are off-trail, jump ahead).

  1. Place your compass on the map with a corner of the straight edge on the landmark you identified and your travel arrow pointing in its direction.
  2. Keeping the corner on your landmark, swing the compass so that the magnetic arrow is lined up with the north-pointing orienting arrow, and the orienting lines align with north/south lines on the map.
  3. Draw a line along the straight edge of your compass to your trail; You Are There.

 

If you’ve wandered off-trail, or don’t have another linear feature to work with, you can use triangulation to narrow down your location on the map.

  1. Find two additional landmarks that you can see in real-life and locate on your map.
  2. Follow the steps above, shooting a field bearing of each landmark and then transferring the corresponding line to the map.
  3. Most likely, drawing each line from your field bearings will create a triangle on your map; if done correctly, they will intersect or create a small triangle in (or near) which you’re located.

“Don’t talk yourself into something that isn’t there,” says Jhung, an avid trail runner and former adventure racer. “I’ve been up the wrong 9,000-foot mountain, looking at the [correct] checkpoint on another peak, and down the wrong valley in the middle of the night.” When lost, she says, “You have to backtrack to where you know you are on the map.”

To gain proficiency in map and compass use, it’s a good idea to take a class (offered at outfitters like REI). There’s no better way to learn than to practice under the instruction of a certified guide.

 

For more on trail navigation, visit the “safety and navigation” chapter of our new online how-to guide, How to Trail Run.

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