This chapter is the core of the book, in which the underground shelters of Cappadocia are examined in comprehensive detail and evaluated from a variety of perspectives. Following an initial overview, the opening section examines the various typologies of these shelters and the standards associated with them. The date of the first construction of these structures is a topic of contention in numerous articles. The third section will present these disparate views and engage in a discussion of the dating of these structures. It is of equal importance to consider the defensive devices within the underground shelters and the defensive designs of these structures, which will be discussed in the following section. The subsequent section examines the techniques utilized for subterranean excavation in Cappadocia, with a particular focus on the methodologies employed in the excavation of these structures. The sixth and final section presents an inventory of 253 underground shelters that have been identified within the region to date.