How many books are there in the Icemark Chronicles?

Three Twig, three Rook, three Quint, the Immortals and the lost barkscrolls. 11.

There are 13. The Quint Series = 3, Twig series = 3, Rook series = 3, then there is the lost Barkscroll, the Immortals, The Stone Pilot, The Edge Chronicle Maps.

9, and they are all published. However, they have been writing several stand alone books to go along with the series.

There isn't really any set number of books that are coming out. However, the author Joseph Delaney signed a contract for the 8th and 9th books. So you can look forward to at LEAST 9 books, although...

I heard it was a trilogy, which means the Kane Chronicles will have three books in all.