This essay will examine urban design in terms of the changing modalities between the « built » and the « viewed » in France from 1200 to 1600. The Italian Renaissance ideal of disegno, while important, did not displace enduring medieval traditions of urban design and innovation. Geometric theory and practice, long in separate realms, gradually merged after 1500 to create a new visual culture and directions of urban design brought about by improved projective mathematics, its use by surveyors and cartographers, and advances in etching and printing methods. Urban design and maps relected new ideological values and ambitions embodied in the new bastioned trace and the rationalizing urbanism of the monarchical state. Innovative medieval craft practices combined with new technologies and evermore robust, bureaucratic forms of public governance to reshape urban life in the modern forms recognizable today.