This is the 50,000-year story of the Australian Aboriginal rock art of Arnhem Land. Aboriginal rock art, as practised in Arnhem Land, is the world's longest continuing art tradition. It is a tradition that is not merely decorative, but provides a "journey in time" - a pictorial record of the longest surviving culture on earth. Occurring at thousands of different sites, and of many different styles, the rock paintings of this region date from at least 30,000 years ago, and some may have been in place as early as 50,000 years ago. The oldest galleries pre-date the Hall of Bulls and Lascaux in France. This book explores the depth and complexity of this art tradition and gives insight into the aesthetic and cultural worlds of the people who created it. 'Journey in Time' has been written and illustrated with the permission of the Gagudju people, the traditional owners of the land.