Maps (AQA GCSE Geography): Revision Note

Maps

• Questions in the exam will be based on topographical maps 

  • The maps can be from anywhere in the world

  • Maps will have a key, scale, northings and eastings

  • These all need to be used to answer the questions

Grid references

• 4-figure are used to locate specific grid squares within the map

  • The first two figures are the eastings, which indicate how far east or west a grid is across the map

  • The second two figures are the northings, which indicate how far north or south a grid is on the map

• 6-figure grid references are used to locate exact points within grid squares

  • The first three figures are the eastings 

  • The second three figures are the northings

• To find a 4- and 6-figure grid reference

  • To find the four-figure grid reference, give the number from the bottom of the map first, then the number from the side 

• In image above, the 4-figure grid reference would be 17 51

  • Ordnance Survey four-figure and six-figure grid references are written as a sequence of numbers without commas between the digits

• To give the 6-figure grid reference, you need to image that the grid square is divided into 100 smaller squares 

Scale 

• Maps in the exam will either be scale 1:25,000 where 1cm on the map = 25,000cm (250m) in real life or 1:50,000 where 1cm = 50,000cm (500m) in real life

• When the distance is straight or almost straight, it can either be measured using a ruler or the edge of a straight piece of paper.

• Mark distances on a piece of paper using the scale at the bottom of the map.

• You can then lay the paper from the first point to the second point to calculate the distance.

• A distance along a curved route can be divided, the paper rotated and marked in stages to calculate the full distance

• To measure from A to B following the road on the map below, the route can be divided into a series of straight sections using crosses.

• Next, use the plain piece of paper to measure from A to the first cross. Next, rotate the paper, pivoting at the cross to mark the second cross. 

Bearings

• Directions on a map should always be given using compass points

• There are 16 compass points 

• A grid bearing is measured from grid north at 0^o, East is 90^o, South is 180^o  and West is 270^o

• Grid bearings are given using a protractor

  • The 0° should be pointing north and the centre of the protractor should be on the place the bearing is been given from

  • The compass direction and grid bearing from the crossroads at A to the location at B

• On the map above, B is southwest of A 

• The bearing is 280^o

Height

• Height can be shown in three main ways:

  • Spot height

  • Contour lines

  • Trigonometrical stations

• Spot heights show the height at a specific point with the height measurement written next to it

• Contour lines are isolines. They join points of equal height and are usually at 5- or 10 metre intervals (distance between the contour line)

  • This means that the height of the land increases by 5 or 10 metres between the lines

• Trigonometrical station is marked by a small black triangle with a height measurement written next to it

Topography 

• The contour lines can also indicate the shape and slope of the land or topography

• Contour lines close together indicate steep land

• Contour lines very far apart indicate gently sloping or flat land, depending on the distance apart

• V-shaped valleys have a v-shaped set of contours 

• A hill is shown by a set of circular contour lines

Cross-sections

• A cross-section is a slice through the landscape

• They are represented on a map by a line which is often labelled A at one end and B at the other

• They use the contour lines to determine the height of the land

• A piece of paper is then laid along the line and points A and B are marked on

• The contour lines are then marked on each time they cross the paper

• These figures can then be used to create the cross-section 

Key

• Maps can be used to identify a range of landscape features

• These may be physical and human features

• Each map has a key to show what the symbols mean