Map Reading

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Map Reading

• CWO Richard Atkin

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Maps

• Its a written document helping a person go from
  place to place
• Use scales to represent large areas of land in a
  small space
• Smaller the scale, the more detail covered
• Eg. 1 10,000 (1cm 100m) Orienteering
• Eg. 1 50,000 (1cm 500m) Walking
• Eg. 1 1,000,000 (1cm 10km) Long distance
  flying

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Things on a Map

• Items on a map are represented by symbols
• Natural Rivers, Valleys, Hills, Streams, Woods,
  Mountains, Marshes
• Man-Made Roads, Canals, Railways, Towns,
  Villages, Power Lines
• Contour lines used to show gradient of land

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Grid Referencing

• To pinpoint position, a system known as grid
  referencing is used
• The Earth is split up into sections, each of
  which has a number
• A grid is then placed on the map using these
  numbers
• Get position by taking number of the line going
  across and number of the line going up
• along the corridor, up the stairs
• Gives a set of co-ordinates
• Anyone in the world can locate your position with
  the grid reference

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Distances

• Each map provides a scale of how far 1km in real
  life is on the map
• Use a piece of string to measure the distance of
  desired route
• Put the string on the scale to work out total
  distance travelled

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Gradients

• The closer together contour lines are the steeper
  the land
• Height of land is given as a number on each
  contour line check units
• To work out steepness, compare the change in
  height of land to distance travelled and put into
  a ratio
• Eg. 200m height, 1000m distance 15
• If ratio is small then steep slope, if ratio is
  large then gentle slope

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Land Profile

• Draw a picture of what is shown on the map
• To get an elevation, cut the plan in half
• Work in layers
• Bottom to top

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Line of Sight

• Use maps, land profiles and line of sight
  together to get an accurate picture
• Look for a feature in real life and then find it
  on the map
• Line of sight on its own can be inaccurate
• Eg. Distance/Steepness may be greater than you
  realise
• Eg. There may be difficult terrain or obstacles
  to pass in order to get to the feature

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Map Reading

• CWO Richard Atkin
• END