Shrieking Shack
Toward the end of the novel, a climactic event takes place in the shack where the primary revelation occurred in the book Harry Potter and the Prisoner of Azkaban. This shack is hidden by the Whomping Willow, a violent tree Harry and Ron had an encounter with on their way to Hogwarts in Harry Potter and the Chamber of Secrets. The use of imagery here lets Rowling draw out the reflection which precedes Harry's entrance, and it allows the reader to have a sense of catharsis for what happens next in the war between Voldemort and the Wizarding World.
Tent
Harry, Ron, and Hermione must live in a tent for most of the novel. The first time we saw a Wizarding Tent was during the World Cup of Harry Potter and the Goblet of Fire, the fourth book in the series. At that point, Harry was amazed that so much could be packed into what looked like a small tent from the outside; this time, we know the details of the tent because the characters are hidden in there for their own protection.
Graveyard
In yet another moment that reminds us of earlier plotlines in the story, Harry sees the graveyard in which his parents were buried. The seventh book, Harry Potter and the Deathly Hallows, shows his destiny become apparent and his choice to stand for good instead of to give up. This reminder of his parents' mortality allows Harry to fill in the visual gaps to his previous dreams about their graves, and it provides the reader with a stunning glimpse of loss and trepidation.
The Headmaster's Office
Harry enters the Headmaster's office for its Pensieve to understand finally what he must do if he is to win the war. He has been to the office so many times throughout the series, and the reader is well-aware of its spatial location. Because we know how the portraits of the Headmasters are arranged, we are able to place the details of events that occur during Harry's time at the school; we are also able to appreciate the revelation of Snape's memories in the Pensieve.
