This is the core setting product for Glorantha under 3rd ed. RuneQuest. It consists of three books and a folding map of the continent of Genertela, the primary setting for Glorantha-based games.
Book 1, the Glorantha Book, gives a general overview of the world's geography, history and cosmology.
Book 2, the Genertela Book, concetrates on the titular continent. The major regions, nations and peoples are covered with detail maps for many areas shown. This is the main book of the boxed set.
Book 3, Player's Book: Genertela, deals with creating characters from the continent and includes optional tables for determining region, race and occupation.