Dickens does something very interesting with the various locales the Pickwickians visit. Each is given a distinct emotional coloring according to the action that takes place there, but the action is a reflection of Mr. Pickwick's education. By this we mean that what happens to Mr. Pickwick in the places he visits has a direct bearing on his stage of development, and vice versa. There is a definite pattern to the locales.
At the hub of the novel is London, the home base of the Pickwickians. This is the center to which Mr. Pickwick makes periodic returns. London is also the place where most of Mr. Pickwick's education takes place, the moral testing ground, as it were.
When Mr. Pickwick and his friends head for Rochester they are as innocent and gullible as very young boys. The Rochester area, which includes Dingley Dell, lies due east of London. And through the ad-ventures that happen there we come to associate the area with knock-about farce and trusting innocence. Dingley Dell represents a kind of Eden.
When Mr. Pickwick and Mr. Wardle chase Jingle to London, London acquires associations of dishonesty and sharpness. Mr. Pickwick returns to Dingley Dell only to leave it immediately. His innocence has been badly dented, and he returns to London.
The next series of adventures takes place in an area northeast of London, at Eatanswill (Norwich), Bury St. Edmunds, and Ipswich. The keynote to this area is deception. There is the wire-pulling behind the Eatanswill election, the fakery of the Hunter party, the practical joke of Jingle and Job Trotter at Bury St. Edmunds, and the delusions of the Nupkins at Ipswich. In the middle of this section Mr. Pickwick makes a short visit to London because he is enmeshed in a concocted lawsuit, and London acquires further associations of chicanery.
After all of this emphasis on deception, Mr. Pickwick and his friends make a Christmas trip to Dingley Dell, as if to recharge Mr. Pickwick's faith in human goodness.
Back in London, legal trickery wins as Mr. Pickwick loses the lawsuit. The Pickwickians then go to Bath, which lies west of London. Bath is a center of social snobbery, but Mr. Pickwick goes to Bristol, where he finds himself involved in aiding Winkle's romance. At this point the emphasis of the novel begins to change. Deception fades as Mr. Pickwick's positive qualities come to the fore.
In London again, Mr. Pickwick goes to debtors' prison for three months. London begins to seem like the meanest, most treacherous, saddest place on earth from the inside of prison. But Mr. Pickwick changes this outlook as he displays forgiveness and charity toward his enemies and self-sacrifice toward Sam Weller. Mr. Pickwick and Sam rise above the squalor of prison; they single-handedly humanize the place for us. Once they are released, London loses much of its nastiness.
Mr. Pickwick then undertakes a romantic adventure to Bristol and Birmingham on behalf of the Winkles, and these locales take on some of this excitement. Finally, back in London, romance takes charge as the courtships and marriages have happy conclusions.
Thus London changes as Mr. Pickwick does, and the various locales take their emotional coloring from his spiritual state. His progress changes the focus of events, which in turn gives each geographical area its special flavor. While we view Mr. Pickwick largely from the outside, Dickens conveys his growth by means of the action, by the way he focuses on the adventures. In this way Dickens was able to show us his hero's moral development through external events. The method is really quite subtle.