Published: Gollancz 2003
Purchased: Waterstones, Cambridge, 2004-02-26, £6.99
OK, this is a weird one.
The world which we encounter is a huge wall - appearing to go on forever both upwards and downwards. The people live on ledges. Their livestock are monkeys and goats.
The principle form of death is falling off.
Our hero is the boy Tighe (pronounced, presumably, Tig-he, since in his village, all names end either in -he or in -she depending on gender), who manages to fall off the wall, and survive. He gets recruited as a glider pilot in a local war. He fights (ineffectually), gets captured, suffers slavery and finally meets a mysterious and distinctly insane person. Eventually, we discover how this world came to be, and what is special about Tighe.
I'm reminded much of Chris Priest's early novel Inverted World, which made a strong impression on me some twenty years or so ago. It didn't really matter that in the end, the physics didn't make sense. It mattered more that the ending doesn't provide any closure. However, it's still a fine piece of high-concept SF.