The purpose of the application is a scholarly catalog of 180 Italian architectural drawings from c. 1575-1620 previously owned by the architect Carl Johan Cronstedt (1707-1777). The catalog presents new proposals for identification and attribution based on current research and careful examination of the material properties of the drawings. The publication will contribute significantly to the knowledge of architecture in Rome around 1600. The first section (110 issues) documents ancient Roman buildings (the Pantheon, the temples of the Roman Forum, the Marcellus Theater, the Triumphal Arch of Constantine and others) as well as works by the most famous architects of the modern Renaissance, such as Bramante and Michelangelo. The second main group of the catalog consists of 70 original projects by Roman architects, including Carlo Maderno and Francesco da Volterra, dated around 1590-1620. These are projects for churches, palaces, gardens, fountains and more, which constitute almost completely unknown sources of Roman architecture. The intention is to publish the volume in 2019 with the German publishing house Hatje Cantz, with which Nationalmuseum has established a collaboration on research publications for some years.