Orientation is to find our location in the field.
Navigation is the ability to know how we are moving in a specific direction in the field.
A map and a compass is that we need to plan our route.
Orient Your Map
When you read a map you must be able to match what you see on the map with what you see in the field and vise versa. To do that you must first orient the map correctly.
Once you have set the declination (Theursaminor.eu – Compass user instructions) map orientation is simple:
- Place your compass on the map with the direction of the travel arrow pointing to the top of the map.
- Rotate the bezel so that N (North) is lined up with the direction of the travel arrow.
- Slide the baseplate until one of its straight edges aligns with either the left or right edge of your map. (The direction of travel arrow should still be pointing toward the top of the map.)
- Then, while holding both map and compass steady, rotate your body until the end of the magnetic needle is within the outline of the orienting arrow. (THE RED IN THE RED)
Now you have the map oriented correctly and you can identify nearby landmarks on it. This optical identification does not need to be accurate and it is very helpful because it allows us to understand the field and plan our moves. Take some time to become familiar with the map and the surroundings before you start your hike. Check on your map often. especially in long hikes. Staying found is far easier than finding yourself after you’re lost.
Drawing our heading on the map
To draw our course on the map, we need to know where we are and where we want to go and be able to match these points on the map. (Theursaminor.eu – Basic instructions for reading a trekking map) But there is also the case, not to know where we are so things are getting a little bit complicated. Let’s get started with the first case.
A. Drawing our heading when we know where we are
An azimuth is precise way to describe a direction. For example, instead of heading “northwest” to get to a campsite, you might follow a bearing of 3150 degrees. (Theursaminor.eu – Compass user instructions). Azimuths are always relative to a specific location. Following the same azimuth from two different places will not get you to the same destination.
A.1 Taking an azimuth from the Map
You can use an azimuth to get to a location any time you know where you are on a map:
- Set your compass on the map so that the straight side of the baseplate lines up between your current position (1a) and the map location for your destination, like your campsite (1b).
- Make sure the direction of travel arrow is pointing in the general direction of that campsite (in other words, it’s not upside down).
- Now rotate the bezel until the orienting lines on the compass are aligned with the north-south grid lines and/or the left and right edges of your map. (Be sure the north marker on the bezel is pointing north on the map, not south.)
- Look at the index line to read the bearing you’ve just captured.
Now you can use the compass to follow that azimuth to your destination:
5. Hold the compass with the direction of travel arrow pointing away from you.
6. Rotate your body until the magnetized needle is inside the orienting arrow. The other end of the direction of travel arrow is now facing the azimuth you captured and you can follow it to your destination.
A.2 Taking an azimuth in the Field
You can also use an azimuth to find where you are on a map.
- Start by finding a landmark that you can also identify on the map.
- Hold your compass flat with the direction of travel arrow pointing away from you and directly at the landmark.
- Now rotate the bezel until the magnetized needle is inside the orienting arrow.
- Look at the index line to read the azimuth you’ve just captured.
Now transfer that azimuth on the map to find your location:
5. Lay your compass on the map and align one corner of the straight edge with the landmark.
6. Making sure that the direction of travel arrow remains pointed in the general direction of the landmark (6a), rotate the entire baseplate until the orienting lines are running north/south (6b) and the north marker on the bezel is pointing to north on the map (6c).
7. Now you can draw a line on the map along the straight edge of your compass (7a). The point where that line from the landmark crosses your trail is your location (7b).
Β. Drawing our heading when we know where we are
When we do not know our position and we are lost, our first concern is to find where we are. After we find that we can draw our heading. The above procedure “Find azimuth in the” field is not enough. This is because our position could be anywhere on the line that joins the landmark with us.
Finding the position on the map – triangulation
If you aren’t on a linear feature like a trail, or you are on a trail but you don’t know where exactly, you can still find where you are on a map by using multiple azimuths .This method is called “triangulation”. To do this, you must use the process “A.2 Taking an azimuth in the Field” and follow the same steps to take the azimuth for a second and a third landmark, preferably those that are at least 600 degrees away from your first landmark (and each other). Transfer the indications on the map. If your measurements are absolutely correct, the lines that you draw will meet at a single point. That single point is your location. If your measurements are not absolutely correct, (this can happen many times), the three lines will form a small triangle. In this case your location is somewhere in that small area. As you can understand, the smaller the triangle is the more accurate is your position. So, if you draw a large triangle, you must recheck your measurements because you have done something wrong during the procedure.
General advices
CAUTION ! You must not always select the shortest route on the map. Criterion for drawing the route must be the total morphology of the field that takes into consideration the altitude differences, potential technical difficulties, existence or not of water, the need of overnight camp and above all, composition, dynamics and experience of the team. The route is better to be designed in pieces so that its correctness can be verified by fixed spots that we have already choose. The right preparation of the route is one of the most important elements of a proper and safe activity. The key points of attention are:
• Planning of the route and separation in individual segments. Use the map to get an “image” about the terrain and the altitude.
• Collection of information for the route from various sources like travel guides, magazines etc. Also by fellow hikers who may have done the route. What we need from the above is to know if there is a need to use special equipment or what are the difficulties of the route.
• Weather forecast
• On-site collection of information from the locals, if that is possible.
• Full awareness of the team’s capabilities.
Sources: www.rei.com