The author asks to what extent a knowledge of the concepts of yoga may prepare the way to a better understanding of Indian archaeology. The yoga at the basis of this study is that which forms the core of the Tantras. In the first chapter the author surveys the system of Tantrik yoga. He then continues with a discussion of the various forms of yantras, that is all the means employed by yogis in their meditational exercises as aids to the concentration of thought. The author provides in-depth studies of ritual objects of the Lamaistic cult in Tibet and Nepal, the sacred cemeteries of Nepal, and pantheons in Java and Bali.