On the 20th anniversary of the first publication of A Game of Thrones, George RR Martin told the Guardian that a special edition of the book due to be released today on iTunes represents ‘an amazing next step in the world of books.’

A Game of Thrones: Enhanced Edition [offers] ‘a world of additional content,’ said its publisher HarperCollins, ranging from interactive character maps to detailed annotations, character journeys and timelines, family trees [and] audio clips.

The book, which is exclusive to iBooks, includes an extract from The Winds of Winter. Martin said that he was excited by the opportunity to offer readers access to a whole range of secondary material …

“We’re now entering a new period in the history of publishing,” said Martin, announcing the new edition. “The digital book gives readers the ability to experience all this rich secondary material that had not been possible before. These enhanced editions, available only on iBooks, include sigils and family trees and glossaries. Anything that confuses you, anything you want to know more about, it’s right there at your fingertips. It’s an amazing next step in the world of books.”

Enhanced editions of the next four books in the series will be released on various dates between 27th October and March 2017. It’s not yet known when The Winds of Winter will be published, Martin revealing earlier this year that the book was not yet fully written.

The special edition was not available at the time of writing, but should be linked from the original later today.

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