Land Navigation 101

Land navigation can be an invaluable skill when exploring the great outdoors. The best places to explore and go hiking have no roads and lots of vegetation, making it very easy to get lost. If you’ve ever been lost in the woods for any length of time, you’ll know that it’s a very humbling and unpleasant feeling. A little preparation and practice with a some navigation tools can help you stay on track and avoid getting lost.

Before you set out on your next walk in the woods, take the time to learn how to read a map, use a compass, operate a GPS, and use the sun and stars to guide you. Here’s a brief land navigation 101 course with the all of the essential guidance to help you prepare for your next hike or adventure.

Map Reading

• Black: Used for man-made features and cultural areas such as buildings, roads, railways, pipelines, and property boundaries.
  
• Brown: Used for topographic and surface features such as contour lines.
  
• Green: Used to show vegetation features, such as woods.
  
• Blue: Used for water features, such as rivers, streams, lakes, and swamps.
  
• Red: Used for main roads, such as highways. It can also be used to show special features like a tunnel or survey lines.
  

Contour lines are used to connect points of equal elevation. Being able to decipher contour lines and translate them to a picture of the terrain is a handy land navigation skill. Lines that are close together indicate a steep rise in elevation. Often times, maps will label the contour lines with their elevation above sea level. Below are a few examples of what a map will show relative to the actual terrain features that they represent:

If you need a map for land navigation, than taking care of your map can be very important for a long hike. If your map is not water-proof, be sure to protect it in a plastic bag or case. When you fold your map, take the time to do it properly. If you fold your map a different way each time, the creases will become worn and rip and these areas of the map will be unreadable. Depending on your trip and the type of map that you have, it may be worth your while to have it laminated. Most of the larger office supply stores can do this at a reasonable price.

If you’re participating in a land navigation or orienteering course, you’ll need to plot and hike through a variety of bearings and checkpoints, and you’ll also need to gauge the distance that you’re covering between each to see if you’re on track. To do this, you’ll count your paces and compare it to the projected distance that you measured on your map.

To figure out your pace count, measure a 25 meter length on a sidewalk or path, and count your paces to cover that distance. Multiply this number by 4 to get number of paces per 100 meters. Using a set of simple pace beads (like below), count your paces for the first 100 meters and then slide the first bead down. When you reach 1,000 meters, you slide down one of the top beads and reset the lower beads. It may seam archaic…but it works really well! While the use of GPS units has made land navigation a forgotten skill, it’s nice to have a back-up plan for when the batteries die ;-).

Using a Map with a Compass

Having a map is necessary in land navigation, but it’s not very useful without a compass to orient yourself. Once you establish the position on the map where you are (start) and the point where you’re going to stop (finish), the line between them is your path (azimuth). You can take you’re a straight-edge ruler and lightly sketch this path on your map. If you have a protractor, you can measure the compass bearing from the angle of your new line and the map’s vertical north line. If not, don’t worry – there’s another way. Place your compass on the map and turn the map until the north arrow on the map lines up with the with the north arrow on the compass (both map and compass should be on a level and flat surface). If you place your compass at the start of your path, and the north arrow on the compass lines up with the vertical grid-north lines on the map, you should be able to look down and see what direction your path is with respect to your compass bearing. Look at the bearing on the compass that lines up with the direction of your path – this is your azimuth. In the picture below, the azimuth is approximately 330 degrees.

Now that you have your azimuth, you’ll want to correct it for declination. Declination is the angle between magnetic north and geographic north. Declination varies by geographic region and usually noted on topographic maps. As an example, the northeastern states of the US have a declination correction of 10-18 degrees, but the states along the Mississippi River have a declination near zero. To correct for declination you rotate the compass on your map to re-orient the north arrow with magnetic north. Many maps will show the magnetic north arrow and geographic north arrows together with the angle defined between them.

When you start your hike, take your compass and orient yourself and the map so that your facing your azimuth (direction of your path). If there’s no visible trail to follow, you’ll want to use your compass to get a landmark to walk towards, at which point you’ll take another bearing to the next landmark. Land navigation can get tricky in thick vegetation or at night and will require patience and multiple bearing checks. Before you depart, remember your back azimuth (your path minus 180 degrees), as this is the bearing you’ll want to take back to the start.

Below is an example of what the compass sight picture would look like on a lensatic compass when taking a bearing on an object:

Land Navigation...without a compass

There are so many myths and tales out there about how to navigate without a compass...here are the reliable ways:

First and foremost – the sun rises in the east and sets in the west. During the winter months, the sun takes a more southerly track than in the summer months for the northern hemisphere (so it rises in the SE and sets in the SW). But overall, this rule-of-thumb alone can help you find your direction on a sunny day. If you don’t have all day to watch and track the sun’s movement, try this:

1. Put a stick in the ground and mark the top of its shadow with a rock.
2. Wait 15 minutes and place a second rock at the tip of the shadow’s new location.
3. Place your left foot on the first rock’s location and your right foot on the second rock’s location – you’re now facing north.

If you’re in the northern hemisphere on a starry night, locate the big dipper in the sky. There are two stars on the cup of the ladle, opposite the handle. Draw a mental line from these stars and as you pan outward, you should see the North Star, as this is one of the brighter stars in the sky. Follow an imaginary perpendicular line to the horizon – this is north. See picture below.

If you are in the southern hemisphere on a starry night, locate the Southern Cross in the sky. Mentally measure the longitudinal axis of the Southern Cross and extend this axis of the cross approximately 4.5 times in the downward direction. At this imaginary point, take a perpendicular to the horizon – this is south. This one can be a bit tricky – see the picture below for some guidance.

Land navigation is a skill that gets easier with practice and can be aided by numerous navigation tools, such as GPS units. By just the basic land navigation skills above can hopefully help you plot a good path and stay on it. Happy trails!

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