I love this quote:
Walking is the best possible exercise. Habituate yourself to walk very far. The Europeans value themselves on having subdued the horse to the uses of man. But I doubt whether we have not lost more than we have gained by the use of this animal. No one has occasioned so much the degeneracy of the human body. An Indian goes on foot nearly as far in a day, for a long journey, as an enfeebled white does on his horse, and he will tire the best horses. There is no habit you will value so much as that of walking far without fatigue. I would advise you to take your exercise.
– Thomas Jefferson