Trivia: Domhnall Gleeson, who plays Bill Weasley, is the son of actor Brendon Gleeson (Mad-Eye Moody).
Trivia: The scene where Harry, Ron, and Hermione jump into the fireplace to escape from the Ministry was the very last scene to be filmed for the Harry Potter film series.
Trivia: Sophie Thompson, who plays Mafalda Hopkirk, the Ministry of Magic employee that Hermione impersonates using polyjuice potion, is the sister of Emma Thompson, who plays Professor Trelawney in the series.
Trivia: This was the first of the Harry Potter movies to have JK Rowling as a producer.
Chosen answer: Because Harry already knew where the camp was. The protection spells they use (Harry is shown at one point casting them as well) seem to be sort of like the Secret Keeper spell. If you cast them or they are cast on you, it allows you to see through the spells. Also, don't forget that the deluminator led Ron right to the general vicinity of the camp and that the Snatcher team could smell Hermione's perfume through the spells earlier.
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