Why is it unlikely that two contour lines will cross?

Answer 1

Well, isn't that a happy little question. You see, contour lines represent points of equal elevation on a map. If two contour lines were to cross, it would mean that the same point on the map is at two different elevations, which just doesn't happen in nature. So, we let each contour line peacefully hold its own space, creating a clear and beautiful representation of the landscape.

Answer 2

Contour lines never cross because the elevations can't be two different numbers in one spot.