Rules of Contour Lines

1. Every point on a given contour line is of the exact same elevation.
2. Contour lines should never cross one another.
3. Contour lines should not merge.
4. Contour lines never split.
5. Spacing of contour lines indicates the slope of the land
   • closely spaced = steep
   • widely spaced = gentle slope
6. A concentric series of closed contours represents a hill
   • contours with hachure marks represent a depression.
7. Contour lines form a V pattern when crossing streams
   • the apex of the V always points upstream (uphill)