Where It All Goes Down
Henrietta, Virginia
Henrietta, Virginia, isn't exactly your typical small town in America. It may seem that way—it's full of big wooded areas, bored teenagers, and residential neighborhoods—but in fact, it's a very special place. Gansey is initially drawn to Henrietta because he believes that it is where ley lines (spiritual energy roads) can be found. And Blue's family of kooky psychics stays in Henrietta because the spiritual elements of the place make their powers of prediction even stronger:
"Of course," Neeve said. "Henrietta's on a ley line."
That meant that Gansey was right. It also meant Blue knew exactly where the ley line ran, because she'd seen Gansey's spirit walk along it only a few days earlier.
"It's why it's easy to be a psychic here," Neeve said. "The energy is strong." (17.61-63)
Henrietta is a place filled with secrets and magical things to be discovered, and as such, it is a place that brings together curious characters, like Gansey, Blue, Whelk, and Neeve. All of them have their own agendas, but they're drawn to Henrietta's mysterious charms and the promise of something great hidden right in front of them.
When Neeve says that this is why it is easy to be a psychic here, she confirms something that they've all suspected about the place: It's magical.
But it's also dangerous.
Monmouth Manufacturing (Gansey's Apartment)
What kind of teenager owns a giant luxury apartment? Well, that would be a very rich teenager—like Richard Gansey III (known to his friends simply as Gansey). Instead of staying in the dorms at Aglionby like the rest of the student body, Gansey has opted to buy a beautiful old manufacturing building called Monmouth Manufacturing. He's turned it into a living space for himself, Ronan, and Noah:
The high ceilings soared above them, exposed iron beams holding up the roof. Gansey's invented apartment was a dreamer's laboratory […] And everywhere, everywhere, there were books. Not the tidy stacks of an intellectual attempting to impress, but the slumping piles of a scholar obsessed. (4.18-19)
Gansey's living space is a perfect glimpse into his inner life. It's big and obviously comes from money, but it's also filled to the brim with his best friends and books about his greatest obsession—Glendower and the ley lines. In creating his own living space, Gansey has taken complete control of his life, which is what Adam envies in him when he looks at the apartment:
Adam felt the familiar pang. Not jealousy, just wanting. One day he'd have enough money to have a place like this. A place that looked on the outside like Adam looked on the inside. (4.20)
The apartment is a kingdom that belongs completely to Gansey. He can choose who gets to come and stay there, and it is the place where he can carry out all of his research in peace. It's his domain.
Cabeswater
Cabeswater is a pretty wild place—in more ways than one. When Blue and the raven boys stumble upon the woods that make up Cabeswater, they're immediately awed by how nature has turned magical. There are fish that appear out of nowhere, seasons that come and go in the span of an hour, and trees that speak Latin better than any high school student:
The hissing rustle came again, and now, it seemed obvious that it was a voice, obvious that it had never been leaves. Plainly, Gansey heard a crackly statement in Latin. He wished, suddenly, that he'd studied harder in class as he repeated the words phonetically to Ronan. (26.26)
Cabeswater is a wildly unpredictable place where anything can happen, and the normal rules don't apply. Because of this, it's an exciting place for the characters to be—because it leads them to the ley lines—but it's also a dangerous place. And because of its strong magical draw, it is the place where the climax of the novel goes down, where Whelk attempts to kill Neeve and Adam, and Adam sacrifices himself.