In 1992, in the context of the Archaeological Project Teotihuacan 92-94 under the direction of Eduardo Matos Montezuma, two caves in the southeast of the Pyramid of the Sun were excavated. The undertaken research demonstrated the use of these caves by teotihuacanos in a ceremonial context but also by the cultures after the collapse of this great metropolis. This book provides a new interpretation of the research done in the nineties using a wider understanding of the use and function of this underground ceremonial complex. Chronological periods have been updated, and the social models are more adapted to the current interpretations of teotihuacan society and the meaning an function of their rulers from classic to postclassic periods. Also this book is a contribution to the study and understanding of the symbolism of caves in the Mesoamerica cultural area.