Far from being a dark art, navigating with a map and compass can be immensely satisfying. Navigation doesn’t come naturally to everyone, but learn the basics and it’s life changing. You'll gain the confidence to plan walks and explore new ground independently.
This is what this guide is all about: getting you familiarised with a map and compass, teaching the basics of how to navigate with them, laying the foundation for you to head out and practice and hone your navigational skills.
Learning how to navigate with a map and compass promotes you from walker to explorer. In addition to boosting overall confidence, it's one of the key skills required for more challenging winter hikes when visibility can be very poor. It's also necessary for night hiking.
Getting to know a map
The UK is one of, if not the best mapped country in the world, with every crinkly edge, wandering river and twisting highway covered in remarkable detail. And depending on what you need one for, maps come in various scales and sizes, from road atlases to detailed street maps.
But of course, the key is knowing what everything on a map means...
Map scales and distance
Scale is the ratio of distance on the map to distance in the real world and most walkers prefer 1:25,000, with every 4cm on paper representing 1km on the ground. At this scale, maps cover a large area in ample detail. The Ordnance Survey Explorer and Harvey Superwalker series are examples of 1:25,000-scale maps.
At the bottom of every OS map, the scale bar (like the one above) shows metres, kilometres and miles. For navigation, it’s easiest to think in metric distances and heights, as every grid square is 1km x 1km and heights are shown in metres.
Map legends and symbols
On every paper map there’s a legend – the key to every line and symbol, from manmade linear features like roads and railways, to natural features, buildings and landmarks.
Some are quite obvious in what they represent, but it’s worth familiarising yourself with more obscure icons and letters, like pylons, trig points and footbridges, which can be invaluable.
Rights of way are by far the most useful symbols for walkers. Rights of way are just that – the legal right to move over a route – but there won’t always be a clear path or track to follow on the ground. It helps to recognise permissive routes and access land too.
Terrain features – manmade (like walls and hedges) and natural (like scree and watercourses) – are represented too.
Vegetation symbols can tell you what to expect underfoot, from scrub and bracken to impassable marsh and woodland. It’s vital to know these symbols if you’re navigating off-path. Not only do they highlight hazards, their absence can indicate easier routes avoiding difficult terrain.
Heights and contours
On OS Explorer maps, relief – the rise and fall of the land – is shown by contour lines. These orange-brown lines represent the height and shape of 3D hills and valleys on 2D paper.
They’re spaced every 5 or 10 vertical metres apart depending on how hilly the area is (check the legend to be sure) with thicker lines at 50m intervals. Lines are numbered with their height in metres above sea level, which indicate whether you’ll be walking up or downhill.
The closer together the contours, the steeper the slope. Encircled by contour lines at the top of hills and on prominent spurs, you’ll also see numbered dots called spot heights – either orange (air survey) or black (ground survey). These mark the highest points above sea level.
Grid references
Every Ordnance Survey map is overlaid by a grid of light blue lines marking squares 1km x 1km in size. These squares then make up larger 100 x 100km squares, which are identified by a two-letter prefix, found in the corners of every map sheet. Together these squares make up the Ordnance Survey’s national grid.
The vertical lines are called eastings, with numbers increasing from left to right. The horizontal lines are northings, with numbers increasing from bottom to top. The lines are numbered along the edges of the map, and at ten grid-square intervals across the sheet.
You can use these lines to pinpoint any location in Britain using a grid reference. A six-figure grid reference is usually sufficient, which narrows down a location to an area 100m x 100m.
Reading a grid reference is a bit like playing battleships. Let’s say we want a six-figure grid reference for Washfold Gill in the grid square pictured above:
1. First read off the easting: 092
2. Then the northing: 710
3. Add the letter prefix for the full grid reference: SE 092 710
Getting to know a compass
Below is a diagram of the parts of a compass. We'll then explain how to use these to navigate.
1. Compass needle: Red always points towards magnetic north. The reverse part is often white and can be used to follow a ‘back bearing’ (i.e. going back on yourself).
2. Orienting lines: For aligning with a map’s longitude lines when taking a bearing.
3. Orienting arrow: To align with the needle after taking your bearing to establish your direction of travel.
4. Compass housing/bezel: A disc filled with liquid in which the needle, mounted on a pivot, swings freely. The liquid helps it settle quickly, dampening vibration for an accurate reading.*
5. Declination scale: To correct magnetic declination/variation.
6. Romer scales: Some compasses have ‘romer’ scales for measuring distances or taking six figure grid references.
7. Ruler: For measuring distances on maps of different scales which don’t match the compass’s romer scales.
8. Direction of travel arrow: Indicates the direction you’ll be walking when following your bearing.
9. Magnifying glass: For better viewing of small details like close contour lines, boulders, or crags.
10. Bezel ring: This rotates around the compass housing, marked with the cardinal points and a graduated scale in 2° increments.
11. Baseplate: The plate that the compass is mounted on.
12. Lanyard: For extra security against drops – you really don’t want to lose your compass.
*Bubbles in compass housings are often caused by a contraction in the liquid due to cold temperatures or a rise in altitude. Leaving it on a sunny windowsill at home can solve it, but so long as the bubble is less than 6mm diameter, it shouldn’t affect your compass too much. Observe it when taking a bearing to see if the needle is affected.
How to use a map and compass to navigate
Setting a map
To set a map essentially means lining up what’s on paper with the real world. Whichever way you’re facing, the top of the map should point north – so if you’re walking south, the map will be rotated so the writing is upside down.
It's best to use your compass for this (especially in poor visibility), although you can set a map using obvious landforms, landmarks and linear features like walls and paths if you’re confident of your position.
1. Place and hold your compass on the map.
2. Turn the map until the compass needle is parallel with the map’s vertical grid lines and the red end pointing to the top of the map.
3. With the needle and map aligned and pointing north, the map is now oriented in the direction you’re facing.
Taking a bearing
A bearing is the direction from you to your objective (or any given point) and is expressed using degrees. These are the familiar degrees in a circle, where 0° is north, 90° east, 180° south and 270° west. By first looking at your planned course on a map, you can estimate your direction – but to get it bang on, you should take a bearing.
1. Align the long edge of your compass from your location to where you’re going on the map (e.g. point A and B above), with the direction of travel arrow pointing towards your objective on the map.
2. Turn the bezel until the orienting lines are parallel with the vertical (longitude) grid lines on the map, and the orienting arrow inside points to the map’s north.
3. To follow the bearing, lift the compass from the map and turn yourself and the compass until the red end of the needle comes to rest inside the corresponding red orienting arrow. The direction of travel arrow is now pointing to your destination on the ground.
The three norths
There are three different variations of north to take into account when navigating, and here’s what they are.
True north is the direction towards the geographic North Pole, a fixed point on the planet and one of the axis on which it spins.
Magnetic north is the north point of Earth’s magnetic field, which moves over time in relation to changes in the Earth’s core. This is the direction your compass points.
Grid north also known as map north, is indicated by the blue vertical lines on the map. Because mapmakers must try to represent a 3D globe on a flat piece of square paper, this is hard to render exactly.
Beware of magnetic variation! Because magnetic north drifts with time, the magnetic north your compass points to changes too. Variation is the difference between grid north shown on your map and magnetic north shown by your compass.
When magnetic declination is small, you don't need to account for it unless you're micro navigating. But when it's large, you need to compensate for differences between grid and magnetic north using the declination scale on your compass.
First, you need to find out the declination variance from your map. Let's say it's 10° west. Start by taking a bearing as normal using your map, then, holding the compass fixed against your hips, turn your body until the red end of the compass needle points to 10° on the ‘W.decl.’ scale. Twist the compass housing so that the red N arrow on the base aligns with the red N end of the needle again. Then pick a landmark and start walking.
Drift and aiming off
Be aware of drift as you follow a bearing. Over longer distances, it’s better to break your route into short legs, taking several bearings between prominent features.
When heading for an attack point in a linear feature, like a gate in a wall or footbridge over a stream, there’s a risk of drifting off course and missing it. By deliberately aiming off to one side of the attack point, you can be certain which side you’ve hit and can follow the wall or stream to your attack point:
1. Identify your attack point.
2. Identify a linear feature and take a bearing to a point a couple of hundred metres to one side of your attack point.
3. When you reach the linear feature, turn to follow it to your attack point.
Wayfinding, planning, and following a route
Good route planning goes hand-in-hand with good navigation. Before you set off, know exactly where you’re starting and work out the best route to your objective on your map. It helps to mark your planned route in pencil. Consider using a route card too (a list of your waypoints with grid references and distances), and be prepared to adapt your route.
Break your route down into logical legs (of no more than 500m) between easily identifiable waypoints, or attack points, at regular intervals. These could be junctions, high points or landmarks. Look for collecting features, or things to mentally tick off along the way. These could be any spot, linear, or area features from a phone box to a woodland.
When following a route, be sure to look around and checking the map frequently, ticking off the collecting features you expect to see, and watching for upcoming junctions or turns.
Keep track of where you are by thumbing the map – tracking your position across a folded map with your thumb as you move. When you’re confident of following a route using linear features like paths and fences (known as handrailing), the next step is to use compass bearings. This is vital if you’re walking off-path over open ground, but it can also confirm you’re following the right path or handrail feature.
In terms of speed, you can calculate this by using speed = distance ÷ time. You can estimate how long you’ll take by rearranging the formula to time = distance ÷ speed. But you must also factor in the type of terrain and elevation gain.
Navigation manuals and guides we recommend
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The authors of this guide are all part of our experienced outdoor team. Meet our team here.