U.S. topographic maps, issued by the USGS, all conform to certain standards, making reading them easy.
Difficulty Level: average Time Required: 10 minutes
- Thin brown lines represent contours or points of similar elevation. The closer together they are, the steeper the terrain.
- Contour lines form "v" shapes in valleys or along stream beds. The point of the "v" points uphill.
- Blue represents water.
- Green represents orchards and forested areas.
- Purple markings are those that have been "photorevised," or added to the map since the original map was published..
- Red areas represent urban areas, although the maps will often indicate special buildings of significance within the urbanized area.
- Roads and highways are represented in black and red.
- The scale on 1:24,000 topographic maps means that one inch equals 2000 feet