The spiritual function of fierce terrain (in the apophatic tradition) is to bring us to the end of ourselves, to the abandonment of language and the relinquishment of ego. A vast expanse of jagged stone, desert sand, and towering thunderheads has a way of challenging all the mental constructs in which we are tempted to take comfort and pride, thinking we have captured the divine. The things that ignore us save us in the end.
Walking mindfully on the Earth can restore our peace and harmony, and it can restore the Earth's peace and harmony as well. We are children of the Earth. We rely on her for our happiness, and she relies on us also. When we practice walking meditation beautifully, we massage the Earth with our feet and plant seeds of joy and happiness with each step.