A Primer on Orienting

Here's a little guide to orienting using the Universal Transverse Mercador (UTM) system. To use this system you'll need a few tools designed specifically for the job:
1.) A map with UTM gridlines.
2.) A Roamer Scale (AKA square ruler) with variety of scales.
3.) A compass

Map with UTM Grid Lines:

These maps are widely available and will likely be on any legitimate map you buy. However, be sure you know what you're looking for. The map should tell you what metrics it uses in the margin and include the Zone (e.g. 18 Northern Hemisphere) depicted by the map. UTM grid lines are usually in blue and will have a numbering system that looks a bit strange (e.g. Longitude: ⁴⁴05^000mN , Latitude: ²80^000mE). These numbers reference the grid system which indicates the scale of the map in meters.  When combined, the examples given above depict a point on map in Zone 18 of the Northern Hemisphere that is 4,405,000 meters north and 280,000 meters east of the bottom-left most point in the corresponding UTM Zone.

Declination: The discrepancy between Grid North (GN) and Magnetic North (MN) on the map. This is important if you are using a compass to determine your location via triangulation since your compass reading will be offset a few degrees from GN on the map. There's a really good reason why GN and MN are not the same. GN will always stay the same while MN will vary year to year, depending on shifts in the Earth's magnetic field. Also, True North (TN) represents geographic north. It is usually indicated by a star (see image). IMPORTANT: Always keep and up-to-date map that shows an accurate Declination. Being even 1-degree off could send you miles in the wrong direction if you walk long enough.

Scale: The scale is important for calculating accurate distance. It will look something like this (1:50,000). This simply means that you must multiple the units on the map by 50,000 to determine the actual number on the ground. For example, 1 inch on the map would be equivalent to 50,000 inches on the ground. Identifying the scaling system on your map is essential to working with UTM coordinates since you will need to use the proper conversion.

Topographic Lines: These lines indicate change in elevation. The map should tell you how many vertical feet are between consecutive lines. REMEMBER: The closer the topographic lines, the steeper the terrain. Avoid traveling in a direction that is too steep.

                         Roamer:

These "square rulers" are necessary for determining coordinate locations on a map. Whatever coordinate system you use, be sure you have a Roamer that uses the scale appropriate for your map.

Guide to UTM Map Reading:
For a somewhat thorough introduction to UTM coordinate reading, follow this link:
Instructional video for using the UTM coordinate system.

(Very boring but thorough!)

                                                  Compass:

Ok, so you don't really need a compass to identify coordinates on a map. But, if you ever need to physically arrive at that destination, a compass is essential. Also, anyone who ventures into the outdoors for overnight backpacking or long trail hikes should own and use a compass. Using a compass can help you get your bearings, even if in the most general sense. Combine the use of a compass with a map/coordinate system and, with some work, you can triangulate your position down to a few meters. Knowing your position is very important for determining which direction to travel if you get lost. Especially if you must find the most efficient route.

How to Triangulate your location:

1. Get to a position that you can easily identify prominent landmarks that correspond to your map. 
2. Using a compass, take a bearing on a prominent landmark (the straight line that intersects the landmark and your position).                                                                                                             
• Taking a bearing: Point the "orienting arrow" on your compass in the direction of the landmark and take a reading between this direction and magnetic north (example: 24 degrees). 
• Twist the knob on your compass wheel so that the "orienting arrow" is in the direction of the landmark. 
• Remember to correct for declination!                                                                                       
3. Now that you have your bearing represented on the compass, match the "orienting arrow" on your compass with the north line on your map. 
4. Next, line-up the edge of your compass to the landmark as portrayed on your map. With the "orienting arrow" pointing north and the edge of your compass touching the landmark on the map, you should be able to draw a straight line along the entire edge of your compass representing the bearing-line (the straight line drawn on the map that intersects the landmark and your position). 

So far, you know that both you and the landmark fall on the bearing line. However, you do not know where along that line you are located. To determine where you are located along the bearing line, find another landmark and repeat steps 2-4.

You should now have drawn two lines that intersect based on your bearing between 2 landmarks. The point of intersection between the two lines represents your location.

Instructional video for Triangulating and plotting a Bearing