The monumental <em>Pianta Grande di Roma, </em>or Large Plan of Rome, which measures about 5 x 7 feet when its twelve plates are assembled, is a landmark in both cartography and printmaking. The map is considered the first scientific rendering of Rome, establishing new standards of accuracy and thoroughness when it was published in 1748. Devised by the Lombard architect and surveyor Giovanni Battista Nolli (Italian, 1701-56), the creation of the map required over ten years of surveying the city carried out by Nolli and a team of assistants with the help of new measuring devices. In Nolli’s “ichnographic” (also called “ground”) plan, architectural features and the urban infrastructure are reduced to a single horizontal slice, a minutely detailed footprint that conveys dimensions, proportions, and orientations to scale with the utmost clarity.