In this work we try to identify if there exist specific patterns in the orientation of Roman towns and military settlements across the Roman Empire, and whether this can be explained by astronomy, as suggested in a number of ancient texts and latter discussed by contemporary scholars. In order to check if cosmology was present in the urban planning at Roman times we have analyzed the orientations of more than 250 Roman sites located in different regions, from the Roman West to the East, and is the largest dataset of this kind obtained so far. Our results present suggestive orientation patterns and point towards an astronomical intentionality, maybe by the integration of important dates of Roman and pre-Roman calendars into the urban layout.