The book will be the sixth installment in the A Song of Ice and Fire series. The fifth book, A Dance with Dragons, was published in 2011.
The new chapter is told from Arya's point of view, and must come as a slight relief for fans anxious for the next book. Martin has been heavily criticized for his pace of writing -- A Dance with Dragons's publication was delayed several times, and was eventually released six years after its predecessor, A Feast for Crows.
Martin has responded negatively to the criticism in the past. Many fans continually raise concern that the 65-year-old author may die before he finishes the series, an idea that Martin lambasted on his blog.
No release date for The Winds of Winter has been set, and Martin's U.K. publisher tweeted in January that the book would "certainly" not be published before 2015.
The fourth season of Game of Thrones, the HBO television adaptation of A Song of Ice and Fire, will debut on April 6. The season roughly covers the second half of the series' third book, A Storm of Swords.
Read the excerpt here.
[George R.R. Martin]