Lion, Witch and the Wardrobe by CS Lewis
A Celebration of the First Edition!
They open a door and enter a world. NARNIA ... the land beyond the wardrobe, the secret country known only to Peter, Susan, Edmund and Lucy ... the place where the adventure begins. Lucy is the first to find the secret of the wardrobe in the Professor's mysterious old house. At first, no one believes her when she tells of her adventures in the land of Narnia. But soon Edmund and then Peter and Susan discover the magic and meet Aslan, the Great Lion, for themselves. In the blink of an eye, their lives are changed forever. Enter this enchanted world countless times in The Chronicles of Narnia.
This is my favorite of the Narnia books (some of the latter ones bothered me because of how the unlikeable people of Calormen were of a veiled Asian culture, and don't even get me started on "The Last Battle!"). But this one is charming without any reservations.