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Topographic Map Lines, Colors and Symbols

Unlike a regular map, where you mostly see highways and roads, a topographic map provides a more realistic view of th­e landscape. Features on a topographic map include:

  • Culture: roads, buildings, urban development, boundaries, railways, power transmission lines
  • Water: lakes, rivers, streams, swamps, rapids
  • Relief: mountains, valleys, slopes, depressions
  • Vegetation: wooded and cleared areas, vineyards and orchards
  • Toponymy: place names, water feature names, highway names

[source: Natural Resources Canada]

Because the maps show so much information, they have a wide variety of uses. People use topographic maps for engineering, conservation, environmental management, public works design, urban planning and outdoor activities like fishing, hiking or camping.

The first step in learning how to read a topographic map is to understand how to interpret the lines, colors and symbols. On these maps, you'll see large expanses of green for vegetation, blue for water and grey or red for densely built up areas. Houses are small black squares. You'll see big buildings -- your local shopping center, for example -- as their actual shapes.

Lines on a topographic map can be straight or curved, solid or dashed, or a combination. These lines indicate boundaries, contours, roads, streams and more. You'll see these lines in many colors -- brown, blue, red, black and purple. Each color means something different.

A topographic map uses symbols to keep the map less crowded, but it's still chock full of information. The U.S. Geological Survey (USGS) lists the following symbols on its topographic maps:

  • Boundaries
  • Buildings and related features
  • Coastal features
  • Contours
  • Control data and monuments
  • Glaciers and permanent snowfields
  • Land surveys
  • Marine shorelines
  • Mines and caves
  • Projection and grids
  • Railroads and related features
  • Rivers, lakes and canals
  • Roads and related features
  • Submerged areas and bogs
  • Surface features
  • Transmission lines and pipelines
  • Vegetation