Welcome to this deck on cartographic skills. These are the skills you need to read and understand maps, which is a fundamental part of being a geographer. For your GCSE Geography exam, you'll be expected to use Ordnance Survey maps to identify locations, measure distances, and interpret the landscape. We'll cover everything from grid references to contour lines to ensure you're confident with any map you see in the exam.

Ordnance Survey maps are covered by a series of blue lines called the National Grid. These lines allow you to pinpoint any location using a grid reference. The vertical lines are called Eastings, as their value increases as you move East. The horizontal lines are called Northings, as their value increases as you move North. To remember the order, use the phrase 'along the corridor, then up the stairs'. You always give the Easting value first.

The simplest way to locate something is with a four-figure grid reference. This identifies a one-kilometre square on the map. To find it, you look for the Easting line to the immediate left of the square, and the Northing line immediately below the square. This gives you a reference like '34 56'.

To be more precise, we use six-figure grid references. This pinpoints a location to within a 100-metre square. First, find the four-figure reference for the larger square. Then, imagine that square is divided into a smaller 10 by 10 grid. You estimate how many tenths you need to go across for the third Easting digit, and how many tenths you need to go up for the third Northing digit.