Cavity and limit is a book that shows a clear determination to investigate architecture through a specific area of research, that of the limit and its corrosion, of cavity. The book analyzes the built form through two different ideas of making architecture, that of tectonics and that of stereotomic, through the archetypes of the hut and the cavern. The limit and its gradual reduction to simple element of technology and media is investigated; an element now deprived of its strength of matter and space. The author wonders if today it is still possible to defend the thickness, along with concepts such as ground, matter, mass, hollow, shadow, light, space. The book is enriched by a profound reflection on the theme within the preface of Alberto Campo Baeza, that the spanish architect wanted, with enormous generosity, donate.