An Exclamation in the last Narnia book, The Last Battle. The protagonists find themselves in a heaven version of Narnia, connected like a Pangaea to a heaven version of the rest of the world. Everything gets bigger and more wonderful the further you explore.
It's the reverse of the Lovecraftian Horrors Too Unspeakable to Describe. It is also a good device for stimulating a child's creative mind. The story is over, but one could keep pretending that the story is still alive.
Unfortunate side-effect of this device when the child gets older: Fanfic