From the New World Volume 6

Saki and her schoolmates enjoy what they consider normal lives in a peaceful provincial setting. Only their village cannot be of this era. Its customs differ from those of any known in modern day Japan. The landscape while familiar is also much more constrained than what modern day maps may exhibit.

So when 6 friends embark on a journey of mental and physical training, this fateful journey will lead them to a series of mind-shattering truths-for these characters and for us as readers.