Narnia is the fictional world created by C.S. Lewis for The Chronicles of Narnia.
The seven-book series presents Narnia as a world containing talking animals, mythical beings, human visitors, and a long history of kings, queens, wars, and creation. Aslan, the great lion, is its central spiritual and royal figure. The children who visit Narnia come mainly from Earth and experience different periods of its history.
Narnia is not the name of the series itself; the series is called The Chronicles of Narnia. That distinction matters because individual books have separate titles, including The Lion, the Witch and the Wardrobe and The Last Battle.
Lewis’s world should also be distinguished from J.R.R. Tolkien’s Middle-earth and Ursula K. Le Guin’s Earthsea. Narnia draws on Christian symbolism, Greek and Roman mythology, fairy tales, and medieval romance, but it is not presented as a direct allegory in which every character has only one fixed counterpart.