I'm a secondary English teacher, so I often 'check out' children's literature to make recommendations for my pupils who don't like to read. The first Garth Nix book I read was Mister Monday, which although thoroughly absorbing and enjoyable is clearly written for pre-teens. So, I was wonderfully surprised when a librarian recommended Sabriel to me as this novel is definitely meant for late teens and/or adults.
The Abhorsen Chronicles is a trilogy of three novels. Sabriel is a dark, rites of passage masterpiece that rivals Lord of the Rings. It is a stand-alone novel, but as Nix created such a believable world, it is no surprise that he then created the sequels: Lirael and Abhorsen - these two books need to be read one after the other to truly appreciate the writer's craft. Not only is Nix blessed with a wonderful way with words, he is also very skilful in creating a complex web of intriguing storylines that have real meaning by the end.
I would recommend this to young adults who enjoy Harry Potter or Lord of the Rings. I am sure you will also struggle to put the book down, fall in love with the characters and dream of the Old Kingdom existing somewhere out of sight in our world, just waiting to be discovered.