Main Street
In the short Introduction which precedes the opening chapter, the author affirmatively situates Main Street as an ironic symbol of supreme significance by virtue of supreme insignificance on the course of history:
“Main Street is the climax of civilization.”
The mock majesty with which he symbolically endows Main Street leads to the ironic rhetorical question which the novel sets out to answer:
“Would he not betray himself an alien cynic who should otherwise portray Main Street?”
Trains
As Carol muses upon the importance of trains as a result of not having access to them, she thinks of them through a panoply of symbolic incarnations: “new god; a monster of steel limbs, a deity created by man that he might keep himself respectful to Property.” The massive power of the locomotive to connect small towns dotting the landscape of the entire country together represents for Carol the ultimate potential for escape from one of those dots.
Carol
The author also explicitly situates his protagonist as a symbol of something larger:
“The days of pioneering, of lassies in sunbonnets, and bears killed with axes in piney clearings, are deader now than Camelot; and a rebellious girl is the spirit of that bewildered empire called the American Middlewest.”
The rebellious girl in this novel is Carol and through her rebellion against small town conformity and gossip on the plains, she becomes a symbol of the spirit of American empire.
The Countryside
The countryside and everything associated with it—pastures, woodlands, lakesides, and meadows—represent total freedom from the crushing atmosphere of Gopher Prairie life. Such is the literal freedom that countryside offers that she cries in out to the heavens in thanks for the symbolic freedom its allows her to briefly express.
Village Virus
Village Virus is a symbolic medical disorder coined and described by Guy Pollock. It covers the full spectrum of symptoms that Carol fights so hard to fend off: narrow-mindedness, crushed hope, deferred dreams and conformity.