Jane Austen really loved her threes in Northanger Abbey. The book prominently features three families and three sets of siblings. The action in the book also occurs in three distinct places: Fullerton/Woodston, Bath, and Northanger Abbey. OK, so that is technically four places – Fullerton and Woodston are two villages. But Fullerton and Woodston are also similar types of places, which contrast to the types of places Bath and Northanger Abbey represent. Hence, the threes triumph again.
To begin with, all the action occurs in an unspecified year in early nineteenth century England. All the characters are relatively well off, though some more so than others. The Tilneys are extremely wealthy. The Thorpes and the Morlands, meanwhile, definitely do not have as much money. The Morlands and the Thorpes would qualify as lower gentry; they are at the bottom of the upper class, but they are still at a higher social station than the growing, middle class – or merchant class – that was rising in this period. We've got the social classes set up, so let's see where they hang out. The novel opens and closes with Fullerton, the small village where Catherine grew up. Intriguingly, she explicitly compares Woodston, Henry's home, to Fullerton. Country life and domestic life are generally praised in the text:
Now, there was nothing so charming to her imagination as the unpretending comfort of a well-connected parsonage, something like Fullerton, but better; Fullerton had its faults, but Woodston probably had none. (26.16)
Urban life and high society are depicted in Bath, which is where Catherine has lots of adventures and misunderstandings. Arguably, Bath is the actual epicenter of Northanger Abbey, in spite of the title. The bulk of the action happens in Bath, both good and bad. Being in Bath allows Catherine to socialize in a way that would have been inconceivable in Fullerton – she goes to plays, goes shopping, goes on unchaperoned carriage rides, meets eligible young men, and interacts with totally new people. Bath is definitely where the action is at in this novel.
Northanger Abbey, both the place and the book, could not have happened without Bath. Bath allows for Northanger Abbey. Catherine never would have gotten an invite to go to Northanger Abbey if she hadn't been socializing in Bath. She also never would have gotten an invite if she hadn't been the subject of some rather interesting rumors (thanks, John Thorpe) that really could have only been spread in a place like Bath. Unlike Fullerton, Bath is an urban space full of strangers. In the days before Google searches, it was hard to get solid information on people. People could lie and could get away with it without worries of ending up on someone's blog. So the urban environment of Bath made Catherine known to new people and put her in a position to actually go to Northanger Abbey
Northanger Abbey functions as a real place and a slice of upper-class life and parental tyranny. It also functions as an imaginary construct, a place that Catherine confuses with the books she reads and infests with tragic murder mysteries and secret manuscripts. Bath is where Catherine got into lots of mishaps and misunderstandings and Northanger Abbey is where she gets to learn some lessons and do a bit of growing up. All of this in turn allows Catherine to return home at the end, and later move to Woodston with Henry, as an older and wiser individual. If Bath and Northanger Abbey are the places of comedic adventures, then Fullerton and Woodson are the places where people go to settle down once the hijinks are done.