Contour lines on a topographic map show elevation of the ground. Contour lines on a map that are constructed by connecting points of equal elevation .
some general characteristics of contour lines:
1) They do not cross each other, split or divide.
2) Steep slopes are reprented by contour lines spaced closely. Gentle slopes are reprented by contour lines spaced far apart
3) Contour lines trend up valleys and form a "V" or a "U" where they cross a stream.