Overland is the land above the Underland in Suzanne Collins’ Gregor the Overlander. In my month’s tour of world-building, I squeezed in Overland, although from memory, it is really rather like a normal Earth world, and it is Underland that
Helliconia Spring by Brian Aldiss
Helliconia Spring – the first of the Helliconia trilogy by Brian W Aldiss. It came along at a time when I found the books too large and turgid to get into – I don’t know what I read instead, but