Meg, the witch, had heard about Narnia so decided to take her cat Mog and Owl on a trip through the back of the wardrobe.  She wanted to find Aslan the lion and thank him for defeating the Wicked Witch who was despised by Meg and her witch friends.   Probably her tendency to mix up spells prevented her from actually reaching Narnia.
(Meg and Mog is a series of children's books written by Helen Nicoll and illustrated by Jan Pieńkowski)
Thanks to FrankS for his suggestion for monomonday’s challenge of “The Lion, the Witch and the Wardrobe"