The Lion all began with a picture of a Faun carrying an umbrella and parcels in a snowy wood. This picture had been in my mind since I was about sixteen. Then one day, when I was about forty, I said to myself: 'Let's try to make a story about it.'
[C. S. Lewis, "It All Began with a Picture...", On Stories, and Other Essays in Literature, HarperOne (San Francisco: 2017) pp. 79-80.]
The next fortnightly book will be The Chronicles of Narnia, all seven books. The series got its name from Roger Lancelyn Green around the time of the publication of The Silver Chair.
There is, of course, the question of the order in which they should be read. There are three orders that are immediately on the table:
Order of Writing
The Lion, the Witch, and the Wardrobe
Prince Caspian
The Dawn Treader
The Horse and His Boy
The Silver Chair
The Last Battle
The Magician's Nephew
Order of Publication
The Lion, the Witch, and the Wardrobe
Prince Caspian
The Dawn Treader
The Silver Chair
The Horse and His Boy
The Magician's Nephew
The Last Battle
Internal Chronological Order
The Magician's Nephew
The Lion, the Witch, and the Wardrobe
The Horse and His Boy
Prince Caspian
The Dawn Treader
The Silver Chair
The Last Battle
Lewis himself, in response to a young fan asking whether the internal or the publication order was the better order for reading, said that possibly it did not matter, since the whole series wasn't planned out beforehand. He's usually thought to have preferred the internal order, but I think his actual comments are more ambiguous than that; others have noted that he never changed the order of the series himself. I remember when I was in elementary school that librarians were plugging the internal order, and this has become common today. However, there seems to me to be a fundamental problem with the internal order: the entry into Narnia should be by wardrobe. The story structurally works better if it begins in medias res, in the thick of the tale. (For one thing, The Magician's Nephew works better paired with The Last Battle as a sort of higher-order comment on the rest, especially since the story makes more sense on assumption of familiarity with Narnia.) And the whole thing began with a picture about Faun. I just can't get on board with an order that doesn't start with The Lion, the Witch, and the Wardrobe.
But it is true that Lewis was not primarily concerned with matters of order. So I think for this reading I will go with the order in which Lewis is generally thought to have written the books, in which the beginning of the tale is the end of the series. It also has the benefit that The Dawn Treader and The Horse and His Boy pair very well (adventure from and to Narnia), as do The Silver Chair and The Last Battle (the darker books of the series, both concerned with deception).
Somewhere I have the Focus on the Family adaptation on CD, so I might dig those out for a re-hearing.