Map Reading Skills – An Introduction

Home Blog Maps Map Reading Skills – An Introduction

A beginners guide to map reading skills

If you’ve decided it’s time to #GetOutside and explore, a good map is going to be your best friend. At Dennis Maps we print some wonderful maps, including the much-loved Ordnance Survey series covering the UK. Some basic map reading skills will help you to plan your adventures and stay on track when you’re out and about.

Grid Reference system - map reading skills
© Crown Copyright 2018 OS 100050331

A map is a representation of the ground as seen from above, drawn to scale and including symbols that show features of the landscape and built environment. Please click on the images for an expanded view.

OS Explorer maps – the orange Ordnance Survey (OS) Explorer maps are on a 1:25,000 scale, which means that one unit on the map represents 25,000 units on the ground. 4 cm on the map shows 1 kilometre, which allows for a lot of detail. Explorer maps are therefore ideal for walking and exploring.

OS Landranger maps – these are pink and have a scale of 1: 50,000, which means 1 kilometre on the ground is shown by only 2 cm on the map. So they are useful when you are covering more ground, in a car or on a road cycle.

Symbols – map symbols often look exactly like what they represent – a beer mug for a pub, or a blue ‘P’ for parking, for example. Every map has a legend or key at the side that explains in detail the different kinds of buildings, paths, roads, woodlands and boundaries.

All OS map symbols - Map Reading Skills copy
© Crown Copyright 2018 OS 100050331

Contour lines – the thin, wavy brown lines are contour lines that show the shape and height of the landscape – and do not appear on the ground! The map key tells you whether the contour lines are 5 or 10 metres apart. A shallow slope is depicted by contour lines that are far apart. When the lines are close together, there is a steep slope. Look along the lines and you will spot brown numbers that show the height of the ground above sea level.

Contours on a map - os map symbols - map reading skills
© Crown Copyright 2018 OS 100050331

With a little practice of your map reading skills you will be able to look at a 2D map and get a fair idea of what the landscape looks like in 3D, which is helpful in planning your outdoor exploration. The distance you aim to cover may not be long but it will still be arduous if the terrain is rugged.

Grid references – OS maps are criss-crossed with thin blue lines making up a grid. Each square on the grid is numbered from left to right and from bottom to top. The horizontal squares run from west to east and are called eastings. The vertical squares are numbered from south to north and are called northings.

These numbers are used to create grid references that identify a place on the map. Find your grid reference by running along the eastings at the bottom of the map until you find the number to the left of the square you’re in, and then up the northings on the side to the number at the bottom of that square. These two numbers, written in this order, provide your 4 figure grid reference.

© Crown Copyright 2018 OS 100050331

On the orange Explorer maps you will see that the squares are further divided into tenths along the edges of the map. You can precisely pinpoint a location such as a building with a 6 figure grid reference. To do this you look at the square and estimate how many tenths the location lies along the line. Then how many tenths from the bottom. Add these numbers to your grid reference after the easting and northing.

In addition to using your map reading skills on the paper folded maps you can also access Explorer and Landranger maps on your mobile, tablet and desktop. Aerial imagery provides a 3D view and brings the map to life, and an Augmented Reality feature labels interesting places within the landscape to help you explore.

A 7 day free trial is available at

You might also like:

Further information on map symbols.

Planning a walk with an OS Map.