How to Set the Map.
Updated: May 1
Setting the map is one of the most basic but important habits to form when reading a map. You might also hear it called orientating the map. Put simply - when you set a map, you are making it face the right way.
Setting our map helps us make sense of the landscape around us, keep track of our location as we progress through our journey and figure out where we are when we have 'switched off' for a bit.
To understand the process, it helps to understand the 'three Norths'.
Grid North is North on your map. The top of the page. Grid North is very closely aligned with true North, though there will be a small difference.
True North is the North pole. The top of the world. For now, we can ignore this one as we assume that magnetic north and true North are in the same direction.
Magnetic North is the direction that your compass needle points to. This is a slowly but very constantly moving point. In the UK in 2020, magnetic North very closely aligns with true North. In other parts of the world, they are much less aligned and the difference is called magnetic variation.
When we set the map, we are aligning grid North with magnetic North.
When you look at a map, you are imagining yourself being at a specific point on it. You look at the map and ask yourself the question, "If I am here, then I should be able to see such and such feature over there'. When you have set your map correctly, if there is a river in front of your point on the map, there should be one in front of you in the real world. This works with any feature.
Setting your map should be a routine. It should be an automatic action after you get your map out. Every single time you look at a map, you should be setting it. It should become so routine it is subconscious.
Map comes out - map gets set. Map comes out - map gets set! Remember that.
There are two ways you can set your map. The first and most reliable way is to do it with your compass. This works well when the weather is bad and you can't see many features around you. You can practice this at home.
To set your map with a compass:
Place the compass on top of the map.
Rotate the map until grid North matches magnetic North, making the map grid lines parallel with the red part of the needle. North to North.
Grid North is the top of the page when the place names are the correct way up. There will occasionally be one or two that aren't - go with the majority.
The first time you take your map out on each walk, set it like this is. Doing this will help your senses tune in to the landscape and can also help to check that your compass is working.
You should use this method in poor visibility or if you haven't looked at your map for a while.
You can also set the map by eye.
To set your map by eye:
You need to be able to recognise the features around you. This works well with obvious, easily identifiable features such as lakes, buildings, roads, rivers, cliffs, mountains and woodland. It is a good technique for when you are walking on a nice day with good visibility and regularly checking your map.
Rotate the map until an obvious feature that is in a certain direction to you on the ground is in the same direction relative to your location on the map.
You don't have to know exactly where you are to set your map by eye but by setting your map correctly, you will have a much better chance of figuring it out.
A correctly set map, along with the ability to identify landscape features in your immediate area is foundation to confirming your location correctly.
The better at recognising features you get, the easier your job will be. Sometimes, you might literally only have contours to help confirm your location. In a situation like this, without setting your map accurately, you'll be stuffed. When you can locate yourself on a map using only contour features, you are approaching ninja level.
Setting your map is one of the most important habits you must form to read a map accurately.
Setting you map should be done every single time you get it out - map comes out, map gets set.
Setting your map means matching North on your map (grid North) with magnetic North on your compass.
You can set your map by sitting your compass on top of your map and turning the map until grid North runs parallel to the red part of your compass needle.
You can set your map by eye by matching features on the ground with features on the map, so they are both in the same place relative to you.
You can try this at home if you want. If you have any questions about it or would like to come out and do a day learning some skills, please contact me via email.