The first book of the 20th Century Tunja´s collection presents the general conditions of herself, which covers the entire 100 years of the century, with specific periods of analysis defined by cuts in 1905, 1939, 1957, 1989, and 2005. The descriptive and qualitative methodology used by the local press as a fundamental research source is mentioned. In the theoretical framework, concepts such as urban history, urban agents, structural analysis of the urban form, urban morphology, morphogenesis, and typology are clarified. On the other hand, the investigative background of the subject in the international, spanish, colombian, and local contexts is presented. It also advances the general conclusions of Tunja's growth throughout the century.