How to read a map?

Part 3 - How to read a map

Contours - Understanding contours and shapes is a key navigational aid. Above you will see some common contours from any mountain region map. Being able to see that ground on profile in your head vital for good navigation.

The first two images look exactly the same right? So how do I tell based on these images which is which? There are a couple of methods. The first one is to read the contours and what they are doing. On the first image you will see that the contours on the top of the map (650m) are higher than those at the bottom (550m). This indicates a slope downhill or a valley. From image two you will notice the exact opposite is happening. That however is only half that story.

The other method is to use the colours on the map (purposefully left out above for demonstration purposes) On a standard OS map there are colours to indicate higher ground and lower ground. On Irish OS maps the darker the colour the higher the ground. Light Green is the lowest ground while Brown is the highest. Cream and different shades of Brown are used to show varying levels in between those colours.

From Image one above visualise that the valley is a light brown colour and either side of it is a darker shade of Brown. This will very quickly tell you what the ground is doing either side of the valley or spur. (High to Low to High will indicate a valley, Low to High to Low will indicate a spur or a ridge - see image below showing a valley, the high ground shown in the darker shade of brown and the valley to the left in the light shade of brown / cream)