E. Nesbit wrote: "There is a curtain, thin as gossamer, clear as glass, strong as iron, that hangs forever between the world of magic and the world that seems to us to be real."
The Enchanted Castle circumnavigates this boundary between magic and reality. There are four children at the center of this classic children's novel: three siblings, Jerry, Jimmy and Kathleen, and the "castle" housekeeper's niece, Mabel, whom they meet while exploring the castle grounds. She is dressed in a pink gown, and is pretending to be a sleeping princess who must be awakened, a la Sleeping Beauty, with a kiss. This is a very classic British children's fantasy, and although I can't say that it is my favorite by Edith Nesbit, it is a good example of her work. In a Nesbit book, there is generally some sort of magical device or place that is stumbled upon by average, typically upper-class, British children, high jinks and mayhem ensue because the children's manipulation of the magic tends to go badly awry, there is some mild danger generated by the situations in which they find themselves, the children ultimately develop a respect for and understanding of the rules by which the magic operates, and then there is a happy ending of some sort.
As Kathleen said, "I think magic things are spiteful. They just enjoy getting you into tight places."
The Puffin Classics version is recommended - it is a relatively inexpensive version, and is going to be far better than any of the junky print-on-demand books for sale on amazon. The illustrations are included in the Puffin Classics publication, although this isn't a book where the illustrations are of supreme importance. All of Nesbit's works are out of copyright, so anyone can throw a OCR'd kindlebook or POD book up for sale. Purchasers are always better off with a book published by a reputable publisher like Penguin. If you are going for the kindle version, try the free one first, and see if it is miserably formatted before spending money on a version that may not be any better than the free one.
Fans of E. Nesbit may also want to check Edward Eager, as his books are written in much the same style and are also completely wonderful (truth be told, I prefer Eager to Nesbit. Heresy, I know.)