Navigation and feature recognition

In the last blog on navigation we had a brief look at map scale allowing us to appreciate how distances on the ground and the sizes of objects/ features are represented on maps of different scales.

This blog follows on and is aimed at acquainting you with some common symbols used on the OS maps which will help you to extract accurate information when planning the leg of a journey. The more features you are familiar with, the more comprehensively you will understand what the map is telling you about a given area of ground.

Any map worth its salt is going to have a Key included somewhere and on the OS 1:25,000 this can be found printed on the map sheet in the area directly next to the card sleeve that the whole map will fold neatly inside of.


OS explorer key found under card sleeve.

Contours. Arguably one of the most important map features to understand is the contour line. These brown lines wiggle there way all over every OS map and each one is joining points of equal height above sea level in metres. This feature will be covered in depth in its own separate blog.


Contours at 1:50,000 scale.

There is a huge array of symbols to help us interpret the man made environment of towns and cities and it is worth having an idea about the more common ones…if you get it wrong here, hey you can just ask someone right!

However for the remainder of the blog we will focus on natural features and their symbols as these are the ones you will need to interpret without mistake in all weathers, on your own or leading groups, at night, tired, hungry, etc.

Woodland. As woodland creatures, bush crafters will no doubt aim to spend as much time as possible in the green sections of the map. Look closer and those (sadly all too few) patches of green reveal yet more detail. The map makers have gone to the trouble of informing us of broadly what kind of trees we can expect to find at a given location; broad leaf or coniferous.

You may occasional spot the symbol used to designate coppiced woodland too. This detail may be completely lost to some outdoor enthusiasts but to the woodland wanderer this extra layer of detail might help to inform where to go foraging for those spruce roots, acorns or hazel drills for the bow drill.

Understandably and for reasons previously explained in the scale blog individual trees are not mapped, rather the symbols denote a collection of trees of a certain type within the wooded area shown in green.


Coniferous woodland.


Predominantly deciduous woodland (note the few conifer tree symbols depicted in Exeter Wood.)

Water features. Even to the complete novice map reader blue lines and larger blue areas are immediately understood to be water. Even very tiny streams in hill country will be mapped to astonishing detail but beware that the smaller the stream the more prone it is in its infancy to change direction or dry up entirely. For this reason it tends to be the more established rivulets and streams in the mountains that have a reliable flow of water the year round that are actually coloured blue and mapped accurately.

Streams/ rivers of less than 2m width will be pictured as a single blue line with any water course wider than this having both its banks mapped separately and the resulting area between coloured blue to show the shape of the river.


Complex series of water features draining from mountain plateau.

Marshy or boggy ground has its own unique symbol also and is well worth remembering when going ‘off piste’ in the hills over open grass land where these areas of wet saturated ground become a common feature and not one to be trifled with if you like keeping your boots and socks dry!

Boulder fields are almost exclusively found in mountainous terrain and most folk will actively navigate to avoid this potentially hazardous terrain where slips trips and falls into rock holes are all to easy. As in the example with woodland each little black dot on your map does not relate to an individual rock on the ground rather it is telling you within this area of map where you see black dots you can expect to negotiate some broken rocky terrain and scree.

It is possible occasionally for boulders of significant size or striking shape to be mapped due to their ease of recognition and use as a navigational feature to orientate yourself.


Very steep ground with associated rock and scree slopes.

Paths. Footpaths, trails, rights of way however you know them and name them this feature can be very easily misinterpreted on the OS map by novice navigators. Again a separate blog will pull apart the detail of this crucial feature and cover how Access and land use is displayed on the OS map.

On the OS 1:25,000 map a single black dashed line is used to map paths. Any green dashed line is used to signify a public right of way HOWEVER these are liable to change over time and so do not automatically assume you will find a physical path on the ground!

The upland areas and mountainous areas of the UK are criss crossed with thousands of small foot paths and the maps of these areas faithfully depict most of them. However maps are not infallible and so it is prudent never to assume that the path you are following will continue to do exactly as shown on your map. We will take a look at reliable methods for keeping on course in later blogs (…i have a lot of blogs to write…)


Converging foot paths in mountainous terrain.

Walls, fences and hedges. You will encounter enough of these even in our remotest landscapes that it is worth saying a few things about these man made features here.

Anything you cannot walk through due to the rules of physics will be shown as a solid line, nearly always black. Any kind of feature edge or boundary that would not physically prevent you from crossing it on the ground will appear dashed, the edge of a track for example. The one glaring contradiction to this is the solid black line of a cliff edge – impossible to cross from the base of the cliff, hazardously easy to cross over from the top in a white-out!

Cliffs, outcrops and steep terrain will all be explored in detail within the contours blog soon.

In summary features are an all important part of your map’s detail which will give you huge amounts of information about an area of land you have yet to step on (how awesome is that!) the more you pay attention to what the map is actually saying the more educated your route choices will become.

A good map will have a built in key ready to use. Every time you see an unknown symbol mapped along or nearby your route, check out the key and remember it for next time, it wont take long to build up a good working knowledge of even the less used symbols.

Lastly and perhaps most importantly good feature recognition skills will allow you to quickly and effortlessly set your map to the ground without the need for any compass work whatsoever.


Adam Logan







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