As noticed by: http://www.avatarchapters.tv
Avatar: the Legend of Korra final air date [confirmed] can be found at the end in the video [final 30 seconds]. Or you can watch the video, building suspense and view over a hundred original the Legend of Korra photos [screens] from the animation series.
The first book is named: Air, which we know since a while.
The first chapter is named: Welcome to Republic City, which we already knew yes.
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