A Worn Path by Eudora Welty

Phoenix makes a periodic journey into town to obtain medicine for her little grandson, who has swallowed lye and will probably never wholly recover. Phoenix has made this journey so often that she can do it by a kind of interior radar, and thus her mind is free to wander while her feet stay on track. She meets only one person on the road, and thus the beginning of the story is dictated by her interior thoughts.