In the opening of Chapter 27, the reader learns that Elizabeth is going to Hunsford to visit her best friend, Charlotte, who has recently married Mr Collins. Hunsford is the name of the parsonage where Mr Collins and Charlotte live and it is in the same neighbourhood as Roslings, the home of Lady Catherine.
It is during Elizabeth's time at Hunsford, in Chapter 29, that Elizabeth informs the reader of her age. She is dining with Lady Catherine when she reveals that she is twenty years old ("not yet one and twenty"). Lady Catherine enquires about Elizabeth's age because she is so shocked by her openness, as she says: "You give your opinion very decidedly for so young a person."
Hunsford is an important setting for Elizabeth in Pride and Prejudice. In Chapter 34, it is the scene of Darcy's marriage proposal, in which Elizabeth's sense of prejudice and Darcy's pride come head-to-head. It also represents a turning point in the book, prompting Darcy to relate to Elizabeth the true nature of Mr Wickham's character, which will soften her prejudice and, eventually, lead her to fall in love.