Measuring distance on a topographical map is not difficult and there are different techniques for you to use when measuring distance.Measuring distance is important because it gives you the opportunity to do two things.First, it will allow you to examine the terrain in the area you will be exploring.Second, it will allow you to establish a timetable on how long it will take you to travel from one point to another.That timetable will be based on your physical capabilities, which would be speed of travel.
My technique to measure distance on a topographical map utilizes a pencil and clean piece of paper.You then will need to look at the Legend of the map. The Legend gives you important information and references about your map. One of those references is the scale of the map giving you distance measurements.
1. Take the sheet of paper and lay it under the scale of your map.The scale will have length in miles and kilometers. The below picture shows the scale with miles and kilometers.
2. Place the corner of the sheet of paper on the zero portion of your scale and then mark out the tick marks on the paper with your pencil. In the below picture you see that the scale on this map has me mark out .5, 1,2, and 3 miles.
3. Next, find your starting point on the map. On this map it is the Turkey Creek Trailhead.
4. Put your scale on the starting point. Use your pencil to begin pivoting on the trail. Continue following the trail using your pencil to pivot your scale along points of the trail.Continue doing this until you determine the length of distance between your 2 points.(See You Tube Video Below). Use a pencil on the map so you can erase it if needed.
Trails are not all straight and using this method allows you to accurately pivot around turns and curves on any trail.This method should be used in your pre-planning method and it can be used in the field as well.You can also use other methods such as using a piece of thread or even 550/paracord, (the strands inside the 550/paracord), to measure a length of trail. You can then take the thread or paracord and use the scale in the legend to determine your distance. This method, using a thread/paracord, can be a little difficult when measuring out tight turns but it is a viable choice to use in the field.
The above technique, (paper and pencil), is a very easy and accurate way tomeasure distance on a Topo map. Please see my video below for further information on this technique.
Land Navigation is a topic I enjoy teaching.Understanding the basics of Land Navigation will make your wilderness adventure enjoyable and more importantly safe.This lesson will discuss how to use a military protractor on a topographical to get an azimuth/bearing.A protractor is an instrument used to help you measure angles (360 degrees) on a map.Protractors come in different shapes.The more popular shapes are:
In this lesson, I will be using a square (military) protractor which I learned to use in the Army.This protractor has the following features:
Mils Scale (6400 mils 1 mil = 17.8 degrees)
Degrees Scale (360 degrees)
Index Point (Center point of the protractor where the baseline and horizontal line crosses).
In this lesson, we will be using 2 components of the above protractor. The (360) degrees scale and the index point.The other components will be discussed later in another lesson. Some individuals cut away the mils portion of the protractor because it is rarely used for land navigation.Units in the military such as the artillery will use the mils scale for accuracy.Below is a picture of a protractor that has a cut away mils scale.The below protractor also has duct tape around its border.The reason you may want to put tape on the back of a protractor is because the black lettering on a protractor blends in with many topo maps. The tape allows for more contrast and it allows you to see the black degree tick marks we will use to get the azimuth.I used gray duct tape but any dark colored tape will work.
Protractor with Mils scale cut away and tape on back for contrast
Find a point on a map that you will begin from when plotting an azimuth. In the below map lets say we are starting from (hilltop #1).
Next find your destination point. In the below map our destination point will be (hilltop #2) .
Draw a line from your starting point, (hilltop #1), to your destination point, (hilltop #2). Use a pencil so you can erase afterwards.
Starting point #1 (Hilltop) to ending point #2 (Hilltop)
Place your index point on your protractor on hilltop #1. Make sure that the baseline is parallel to a nearest grid line on your map. There are many grid lines on a map to choose from so use the one nearest to your starting point, (hilltop #1).
Topo Map Grid Lines to use when signing up your Protractor
Follow the line you drew from your index point to the degrees scale.The azimuth is 327 degrees.This is your map grid azimuth from hilltop #1 to hilltop #2.Now you are ready to convert this grid azimuth over to a magnetic azimuth on your compass.If you use a compass such as the Suunto MC-2G compass you can set the compass to the magnetic declination of your topo map so no conversion is necessar. If you need to convert the grid azimuth because you do not have this feature on your compass then go to this article I wrote on how to do so, Magnetic Declination
327 Degree Grid/Map Azimuth
Basic land navigation is becoming a lost skill.This skill is being forgotten because of modern day technology, (GPS units), which we all use in the wilderness.I always carry a GPS with me and you should to.Understanding basic land navigational skills will allow you to navigate a wilderness area if this technology goes down or you run out of battery power.I have a section on different land navigational topics/skills here on my website under Backpacking Blog: Land Navigation, for your review.
Land Navigation is a topic that I enjoy writing and talking about. Modern technology, such as GPS units have made it much easier for wilderness backpackers to head out and safely navigate wilderness terrain. I enjoy using this technology, but I also know that this technology can run out of power, (batteries dying), or the satellite network may go down. When these unexpected events happen it could leave you lost in the wilderness. Knowing basic land navigation skills will keep you from getting lost.
Using a map and compass is becoming a lost skill as our society advances. This article is about a basic land navigational skill know as terrain association. Using this method requires you to visually identify terrain features around you. This method can be used without a compass and map but I do not recommend you doing this. You should have a compass and map with you so you can identify these terrain features on your map. There may be a situation for whatever reason that you do not have a compass and map and using terrain association is a field expedient way to for you to navigate.
Terrain association is an ancient method that has been used by adventurers of the past and it is still be used today by many backpackers. Terrain association can help you stay on track or it can guide you from one point to another and back. To use terrain association you need to be able to identify the 5 major and 3 minor terrain features on a map. You may also use other prominent landmarks in the wilderness area such as large boulders, trees, or other objects to help you navigate. Below is a review of the 5 major and 3 minor terrain features.
A drop-off or abrupt change in various terrain. A cliff can be used as a reference point.
Using the above terrain features along with a compass and map is a solid foundation for navigating in ay wilderness area. Using terrain is one technique but you can also use other prominent landmarks to navigate. These can be.
Large boulders, trees, or other land-made structures such as towers.
My favorite way to bushwhack is to use a river, stream, or creek. This feature makes it much easier for you to navigate in all environments or weather. Terrain association has its advantages for quick travel, but it also has its disadvantage when you are in low lying areas where there is thick vegetation and you have difficulty identifying specific terrain features or prominent landmark. In this situation you need to have a compass with a good pace count as you travel from point to point much slower due to the thick vegetation.
Land navigation should be practiced before entering a wilderness area. When you are on your adventure take time to stop and identify these features or landmarks. Many times, backpackers are so involved with getting in the distance/miles and they miss out on the wonders around them. These wonders may save your life or the lives of others when you use them to navigate in a wilderness area.
The World Magnetic Model (WMM) has been updated this month to reflect the new location of magnetic north. This change will affect your magnetic declination that will in turn affect how you navigate in a wilderness area. Scientists from around the world state that over the past decade the Magnetic North has been moving at a greater distance than in the previous years. The movement of magnetic north prior to this dramatic change would average 5 to 7 miles yearly. Over the past decade the movement has been increased to 34 – 36 miles a year. The current location of magnetic north in in the Canadian Arctic. Its current movement is heading toward Siberia.
Magnetic North was located in 1831, by James Ross Clark, a British Royal Navy explorer. Since then we have been able to determine its movement. But with the recent increase in its change the NOAA has put out an update to help those individuals who rely on the location of magnetic north for navigation. This update is usually put out every 5 years with the last update done in 2014. Magnetic north is constantly moving due to the composition of the earth, the earths rotation, and its churring molten inner core.
As a wilderness backpacker I use my compass and a topographical map for land navigation. I use these tools in unison with a hand held GPS unit I bring with me on all of my wilderness expeditions. The new changes in the magnetic north will affect how you navigate in the wilderness, (See my article on magnetic declination). This article will help you convert your map to compass reading or compass to map reading using magnetic declination.
The new World Magnetic Model released this month, (Feb 2019), will allow not only wilderness backpackers to navigate through remote and rugged wilderness areas, but it will also allow many other professions, (Forestry service, , NASA, Aviation related professions, etc.), to accurately navigate.
Bushwhacking is a slang term that backpackers use when they navigate off a trail blazing their own path through a wilderness area. For me it means exploration. Bushwhacking allows you see areas that few have seen and you may find something that has been lost in time. Wilderness backpacking is an adventure and bushwhacking only serves to enhance the experience.
Before you decide to bushwhack I highly recommend that you are up to date and proficient on your land navigational skills. I also strongly advise that you preplan your adventure and research the terrain, wildlife and plant life before you enter any wilderness area.
I recently posted an article on how to prepare for a wilderness backpacking adventure and you can click on the following link, How to Prepare for a Backpacking Adventure, to review that article. I have also posted some land navigational articles here on my website under the Backpacking Blog (Land Navigation).
I will discuss 3 methods I use when I go bushwhacking. Those methods I call:
The Line of Sight Method
The Trail to Trail Method
The Terrain Method
**The above three methods use your compass and a topo map with a GPS unit as your backup. Relying on your GPS alone without having a compass and map is very risky and dangerous.**
LINE OF SIGHT METHOD:
Line of sight is exactly what it means. You are on the trail and you see something in the distance, (some type of landmark such as a hilltop), and you decide that you want to check it out. You first need to find your location on your topo map. If you are not sure where on the trail you are try to find a trail intersection or marker near you that you can identify on your map to assist you in pinpointing your location. Shoot an azimuth/bearing to that point and begin walking.
As you walk use your pace count to determine how far you have traveled from the trail. Stay on course till you reach your destination. As you walk mark your path every 25 yards, (Less or more if you need to), with a rock, stick, or other object for identification if you need to back track. Orient your map to the major terrain features around you such as mountains, streams, etc.
When you get to your final destination mark an identifiable landmark (Tree, outcropping of rocks, Boulder, etc.). This landmark will be what you use to shoot your back azimuth to your starting location. This method is simply to use and it allows you to explore interesting landmarks that you may see off the trail. These points may be structures, terrain features, or other natural points.
As you travel to your landmark, you may come across an awesome area where you may want to set up a basecamp. One advantage in using this method is that you will see the landmark you are traveling too. The hard part is going back if you have not properly identified where you are starting from and a compass azimuth/bearing to your landmark.
TRAIL TO TRAIL METHOD:
This method uses trails on your topo map as linear points that you navigate from to another trail. You basically are bushwhacking from one trail to another. You should first plan your route on a topo map. Find an area you want to do some bushwhacking through with a trail that is close by. Navigate to that trail and then find an adjoining trail. That trail may parallel the one you are on. Shoot an azimuth/bearing to that trail from the trail you are on.
When you are ready to get off trail make sure you can identify your current location on the topo map. Stay on that azimuth/bearing as you explore the area and terrain. If you stay on that course you will run into the next trail which you should be able to identify on your map. You will also want to mark your path as you walk in case you need to back track. Keep track of the distance using your pace count.
You may choose to setup a basecamp somewhere on that course or do some exploration before reaching the trail. If you do stop to explore or setup a basecamp mark a good land mark, (use a Bright vest, a colorful air mat, etc.) so when you are ready to head to that second trail you have a good reference point. You can modify this technique in different ways. You may parallel that second trail knowing that it is a specific direction from you, (North South, East or West). When you decide that you are ready to head to that second trail head in the cardinal direction of that trail.
If you decide to use this method make sure that you can identify where you started from. You may want to use a pencil and draw some lines on your map identifying your route from start to finish. Make sure to keep your map oriented using your compass and terrain features around you.
This method is my favorite and can be used in many wilderness areas. This method allows you to use the natural terrain as a navigational point. I find that using rivers, streams, and creeks, work the best. As you do your pre-planning find a terrain feature such as a river and use it as a navigational tool when you get off the trail. You will not get lost as long as you keep that terrain feature next to you.
I used this method in the Kalmiopsis Wilderness using the Illinois River as my terrain feature. You may choose to use a lake, valley, or even a group mountains or a ridge. I would recommend if you are just starting out that you use a river, stream, or creek. Using a set of mountains or a ridge line can be difficult if you are not proficient in your land navigational skills.
The above three methods will keep you on point when getting off the trail. Remember to have your GPS with you and make sure that it is on and tracking you. If you need to use it to get back then by all means do so. Make sure when you get to your destination to mark it with something that you can use as a reference point to navigate back to your starting point or to another location. As you are bushwhacking you may see a great location to set up a basecamp.
Make sure you have a small notepad and pencil with you so you can write down your pace counts along with your azimuths/bearings. This is especially important if you plan on staying in the area for an extended period of time. If you have never bushwhacked start off slow. Maybe go 100 yards off the trail at first. Then work your way up to larger segments.
Terrain will dictate these methods. You may have to adapt and overcome situations where the terrain makes travel difficult or impossible to traverse. An example would be if you come to a cliff. You will have to back track and recalculate your course. Preplanning is the key to bushwhacking. Look at the terrain before you head out to insure you have a reasonably clear and safe path. Bushwhacking is what a true wilderness backpacker should do to make their trip an adventure.
Trail markers have been around for thousands of years. They are an important navigational tool for Wilderness Backpackers. They allow you to navigate from one point to another. Trail markers allow you to keep in sync with your topographical map. I have seen many types of trail markers while on my Wilderness Adventures and this article will discuss (2) types.
I have defined trail markers in (2) categories. The first being Man-Made Trail Markers and the second being Naturally Made Trail Markers. Both types allow you to quickly identify your surroundings and keep you on course. More importantly they will also give you guidance on getting you back home.
Trail markers have been used by wilderness adventures for thousands of years. In prehistoric times piles of rocks known as Cairn’s were erected to help individuals navigate to and from specific points. They were also used to identify landmarks. So what should you look for when you are in a wilderness area?
MAN-MADE TRAIL MARKERS
Man made trail markers come in variety of sizes and shapes. Trail signs are the most popular and they are found in most wilderness areas in North America. Most trail signs are made of wood but some are made of metal. Trail signs let you know what trail you are on and many of them are used as navigational beacons to point you in the direction of a trail. Topo maps will have these signs on them. Some of these trail signs have a numbers on them instead of the name which should match up to the trail number on your topo map.
A cairn is a man-made pile of stones stacked together. The word cairn from the Scottish Gaelic word (càrn). Wilderness areas with rocks and boulders allow backpackers to construct these rock cairns. On my adventure into the Lost Creek Wilderness in Colorado I saw many of these rock cairns. Rock cairn’s come in various shapes, sizes, and creative designs. Rock Cairns have been around since prehistoric times.
Trail blazing various types of methods to mark a point . Paint can be used to mark a trail. The Appalachian Trail utilizes three colors to mark its trail system, (White, Blue, and Yellow). Paint blazing can be used on rocks, trees, and signposts. Carving is also used as a trail blazing method in many wilderness areas. This practice can be damaging to trees depending on how it is applied. The use of flags/ribbons is another way to guide or mark a trail. The disadvantage of this is that it leaves man-made materials in a Wilderness Area. If you are using it to mark your trail for your return trek you should remove on your return trip. This prevents litter and it keeps the wilderness area in its original state. If it is being used by others as a marker have them remove it as they pass by it.
Indian Trail Marker
There are also Indian Trail Marker. This was a practice used by Native American Indians in the past to shape trees into distinctive shapes. There are many of these markers in Florida and I have seen them throughout North America. Some of these markers are naturally made and may be mistaken as an Indian Trail Markers.
NATURALLY MADE TRAIL MARKERS
Natural or environmental trail markers are markers made by natural events. These trail markers are very unique and they have distinguishable features. These markers can be fungus growing on a tree, rock outcroppings, large trees, downed trees, and many other unique markers. Natural trail markers are subject to change due to fires, storms, earthquakes, or even man-made events.
Knowing and identifying trail markers is an important skill when you are navigating through any wilderness areas. You may want to use your camera and take pictures of these markers as you navigate through a wilderness area. Taking a picture will help you identify these same markers on your return trip. Taking pictures also works very well when you are bushwhacking and off the trail. I have used my camera to help me identify specific areas when I bushwhack. Using trail markers in correlation with a good topographical map will make your stay in a wilderness more enjoyable and it will also prevent you from getting lost.
Pace count is a land navigational skill that every Wilderness Backpacker should know an understand. What is pace count? Pace count is a technique that gives you an estimated distance on how far you traveled on foot. Knowing your pace count allows you to effectively plot your location on a topographical map. It goes hand in hand with other land navigational tools such as your compass. In todays society many Wilderness Backpackers use modern technology, (GPS), to determine their distance. This technology can fail you in a wilderness so understanding and knowing how to use your pace count can keep you safe.
I use modern technology during my wilderness expeditions to determine my distance, but I also use my pace count, especially when I am bushwhacking, to continue my adventure if my GPS goes down. My use and understanding of pace count began in the military. Pace counts have been used throughout history but its origins began in the Roman Legion. Military leaders back then used the strides of their soldiers to determine distances on their march. This has been passed down to other military units throughout the world.
When you calculate your pace count the preferred method in determining distance is using the the metric system. The use of meters and kilometers is how I was taught in the Army. 100 meters equal about 328 feet, and 1 Kilometer equals about 3280 feet (6/10 of a mile). I learned my pace count while serving in the military.
To determine your pace count, you first need to stake out 100 meters on a relatively flat terrain. You walk the 100 meters 4 times getting an average of your 4 splits, (Add your 4 pace counts together and divide that number by 4). When you watch the video you will see that you take 2 steps which equate to one pace. Once you have your pace count tape it your compass so you ill have it when needed in a Wilderness Area.
There are a few ways to keep track of your distance. One way is using Pace Count Beads or Ranger Beads. The other way is to put a small stone or stick in your pocket every 100 meter until you have 10, which is 1 kilometer, or 1 click. The other way is to tie a knot in a piece of 550 cord for every 100 meters. You can be as creative as you want on how you want to keep track of your distance. I find that using a length 550 cord is the easiest way for me to keep track of my distance.
Wilderness Backpackers are modern day adventurers who seek adventures in remote and rugged Wilderness areas. These adventures are exciting but they do have their inherent risks. One of these risks is getting lost. Every year many Wilderness Backpackers get lost when they get off the trail to do their explorations. Even experienced Wilderness Backpackers can get lost. It has happened to me and it is an unsettling feeling that can lead to panic.
When I am on my adventures I enjoy getting off the trail and doing some bushwhacking. Bushwhacking is the best way to immerse yourself and truly experience a Wilderness area. Being prepared before you head into a Wilderness area is essential for a successful and safe adventure.
Before you head into a Wilderness area you should thoroughly research the it online. You should get a topographical map and familirize yourself with the terrain you will be navigating. I always plan my routes, set my waypoints, and look for areas where I can set up my basecamp.
Knowing that you are lost can lead to panic. Panic can cause you to drift farther from the trail you left. Panic can also cause you to get injured or even worse it could lead to your death. Most individuals that are lost are less than 100 meters from the trail they left.
So what do you do when you come to the realization that you are lost? Below is a technique that will get you back to the trail.
A TECHNIQUE FOR FINDING THE TRAIL WHEN YOU ARE LOST
1. When you realize that you are lost stop where you are at and drop your backpack. This becomes your Home Point.
2. Find a landmark within your Home Point. This can be a tree, a large rock, or other landmark. This landmark will become your Navigating Point.
3. Mark your navigating point with something that you can see from a distance so it can be distinguished from other landmarks in your Home Point. This can be your air mat, tent, sleeping bag, or maybe your backpack.
4. You will take your compass and shoot an azmiuth/bearing to your (4) cardinal directions (North, South, East West).
5. Take your first point, lets say you choose North, and you walk out 50 meters from your navigating point staying on your azimuth/bearing. You may want to find an object down range that lines up with your azimuth/bearing.
6. Walk out 50 meters looking for the trail you left. If you do not see anything at 50 meters turn around and come back to your navigating point.
7. Shoot your next azimuth/bearing to your next cardinal direction and do the same thing. Walk out 50 meters looking for the trail. If you do not find the trail come back to your navigating point and go to your next cardinal direction.
8. If you have done your 4 cardinal directions at 50 meters and no trail has been found start the above process all over again but this time go out 100 meters doing the same thing for all cardinal directions.
9. If you do not find the trail at 100 meters then start the process again but now head out 150 meters for each of your cardinal directions. You will increase your distance each time you cycle through your cardinal directions at 50 meter intervals.
Eventually you will come across the trail you left.
The main point in this technique is to establish both your Home Point and a Navigating Point from which you will navigate. If you continue traveling and panic you will become more disoriented and it will push you farther away from the trail.
Tips To Follow For Not Getting Lost
Be prepared before you begin your Wilderness adventure. Make sure that you study the terrain using a topographical map. Research the wildlife, plant life, and history of the area. Knowing these things may assist you if you need to go into survival mode. Plan your routes, waypoints, and possible location of your basecamp using the map and syncing them with your GPS Receiver before heading out.
GIVE YOUR FAMILY MEMBERS OR FRIENDS INFORMATION ON YOUR WILDERNESS ADVENTURE. THE FOLLOWING INFORMATION SHOULD BE GIVEN TO YOUR DESIGNATED INDIVIDUAL BEFORE YOU LEAVE:
The location of trailhead you are leaving from, (Address and/or your Latitude/Longitude).
Your direction of travel from the trailhead (North, South, East, or West).
How many days you will be out.
Your return date.
The name, address, and phone number of the local Ranger Station near you.
Have a satellite communicator with you so family and friends can track you. Your safety is worth the cost of a satellite communicator and many of these units are affordable with different plans.
Have the necessary gear with you. The Wilderness area will dictate much of this but have the following navigating gear with you in order to assist you to while traveling from point to point.
The Suunto MC-2G Global Compass is my compass of choice when I am in a remote and rugged Wilderness Area. What makes the Suunto MC-2G Compass unique is its global needle. On most compasses the entire needle is magnetized. On the Suunto MC-2G the center disk, that the needle sits on, is magnetized and not the needle.
The earth has different horizontal and vertical magnetic pulls around globe. There are 5 regions around the world. If you are a traveler this means that certain regions require that the compass needle be balanced due to these magnetic pulls. Having a global needle means that you can use it practically anywhere in the world. The exception for any compass is when it is used very close to either the Magnetic North or Magnetic South Poles. At these locations navigation with any compass is very difficult due to the extreme magnetic pulls.
So what is the main benefit of having a global needle? The benefit is that the needle can handle up to a 20 degree tilt. This means that the needle will not hit the top or bottom of the compass causing it to lock up. This also means that you are able to stay on point easier and navigate rougher terrain without constantly stopping to re-shoot your bearing.
The Suunto MC-2G also has many other built-in features that I use which makes it a very practical compass:
The Baseplate has a magnifying lens.
There is a mirror that can be used for various purposes such as signaling in an emergency.
There is a straight edge with a scale for determining distance and drawing lines.
There is a Magnetic Declination scale on the back of the compass that allows you to set the Magnetic Declination. Just set it and go.
There is luminous outer ring for low-light reading.
It comes with a quick detachable lanyard.
The Suunto MC-2G compass is a very versatile compass when you are navigating the most remote and rugged terrain around the world. The Suunto MC-2G is also very durable and well suited for rough environments. Below is a video on some of the features along with how to use the compass to do the following:
Magnetic Declination can be a very confusing topic when it comes to Land Navigation. I will try to simplify it in this article. You have three North’s on a Topo map that you have to understand:
True North: The geographical direction that points to the North Pole.
Grid North: The vertical Grid lines on a Topo map which point to your Grid North.
Magnetic North: This is the direction that your compass points.
Magnetic Declination is the difference, (in degrees), between your True North and the Magnetic North (Compass Bearing). On some maps you will see both Grid and True North and the difference between them is very small. Some Topo maps only have True North in the Magnetic Declination Diagram.
If your map does not have a Magnetic Declination Diagram go to this website, NOAA website, to find out the Magnetic Declination in the Wilderness Area you plan on exploring
Magnetic Declination is either Westerly or Easterly. To determine which one you have is very simple. You look at what direction your Magnetic North arrow is pointing. If the arrow is pointing east then it is an Easterly Declination. If the arrow is pointing west then it is a Westerly Declination. Below are pictures showing you an Easterly Declination and a Westerly Declination.
*The arrow that looks like a harpoon is designated as the Magnetic North. In some Topo maps the arrow has a symbol MN. The arrow with the star is your True North.
If you have an Easterly Magnetic Declination then you subtract your Magnetic Declination. To remember this here is a saying you can use:
“EAST IS LEAST” (Least signifies subtracting)
So if your map bearing/azimuth is 180 degrees and you have an Easterly Magnetic Declination of 6 degrees you subtract 6 from 180.
Now your compass is synced with your Topo map. You set your compass to 174 degrees and head to your destination. To convert your compass back to your map bearing/azimuth you add your declination in an Easterly Declination. REMEMBER, the above saying, “East is Least” is to convert Map to a Compass reading.
If you have a Westerly Magnetic Declination then you add your Magnetic Declination. To remember this use the below saying:
“WEST IS BEST” (Best signifies adding)
*So if your map bearing/azimuth is 180 degrees and you have a Westerly Magnetic Declination of 6 degrees you Add 6 to 180.
Now your compass is synced with your Topo map. To convert your compass back to map bearing you subtract your declination in a Westerly Declination. REMEMBER the above saying, “West is Best” is to convert Map to Compass.
You should always check your magnetic declination to ensure that it is correct. You may have a Topo map that is several years old and the Magnetic Declination can be incorrect. Magnetic Declination changes slightly every year.
To find out the current Magnetic Declination in the area you plan on exploring you can visit the NOAA website. This calculator will give you the recent declination that may be different from your Topo map. Below is a short video I posted on my You Tube Channel for further information.