I read this story because the conceit of mapping some other idea onto physical space itself reminded me of Lifelode; in that book, the presence of magic is mapped to how far east or west you are; in The Other Valley, time itself is mapped onto physical space. There is a sequence of towns in valleys each twenty years apart in time; travelling east will let you see the town twenty years in the future. Access to other valleys is tightly controlled for timeline safety and only allowed for reasons of grief.

This book is marginally about time travel and information from the future affecting the present, but it's all in the background of a school friend group that is broken up by a tragic death. The book follows the narrator Odile whose life is pushed off course from this death, made worse by her future knowledge that it was coming.

Stylistically, this book reminds me of Kazuo Ishiguro's Never Let Me Go; they're both dreamy stories of childhood and adult disappointment, focusing on the dynamics of a friends group rather than on details of the world itself. This is definitely not a story that explains its world to you other than the premise, which is taken for granted and creates far more questions than answers. The stylistic choice to not have quotation marks only added to this dreamy quality for me (although I could imagine this is probably controversial for readers).