The eighteen surviving books fall into groups. The first five, the Classic of the Mountains, take up roughly half the text and work through mountain ranges in five directions. The format is relentless and formulaic: so many leagues in a given direction lies such a mountain, on it grows a certain tree or is found a certain jade or ore, in its waters live such fish, and the god of these mountains has a particular form and takes a particular sacrifice.
The remaining books cover the seas and the outer regions: Classics of the Seas Beyond and Within, of the Great Wilds, and a final book on the lands within the seas. Here the register shifts. The formulae loosen and the entries carry narrative, so most of the famous mythological material sits in this second half.
The contents are not sorted into the credible and the fabulous, which is a large part of the point. A mountain bearing recognisable iron and cinnabar is described in the same voice as a country of people with holes through their chests who are carried about by poles, or a beast whose appearance portends drought. Many entries end with a practical note: eat this fish and you will not have boils, wear this plant and you will not be confused, this creature's cry announces war.
Estimates of what it holds run to hundreds of mountains, hundreds of named waterways, and several hundred creatures and deities. No narrative thread connects any of it, and no figure is introduced or followed through. The book is a list, and its myths arrive as incidental detail inside a gazetteer.