How Many Books Are There In The Chronicles Of Narnia Series?

The books are as follows (in publication order):
The Lion, the Witch and the Wardrobe
Prince Caspian
The Voyage of the 'Dawn Treader'
The Silver Chair
The Horse and His Boy
The Magician's Nephew
The Last Battle

When the books were published by Macmillan, they were numbered in the order in which they were published. However when HarperCollins took over the series in 1994, the books were renumbered in chronological order, which was suggested by the author's (C.S. Lewis) stepson, Douglas Gresham.

The chronological  order of the books is as follows:

The Magician's Nephew
The Lion, The Witch And The Wardrobe
The Horse and His Boy
Prince Caspian
The Voyage of the Dawn Treader
The Silver Chair
The Last Battle

Gresham's suggested order for the books was backed up by a reply letter that C.S Lewis had written to a fan who was having an argument with his mother about the order of the series.

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