Roman surveyors (agrimensores or gromatici) implemented at Nicopolis the design principles that characterize the Roman cities of dividing the space into rectangular building blocks (insulae). This roman tradition had been subject to influences from the Greek colonies of South Italy. Before the building of a camp or city, the surveyors, using a topographic instrument called the groma, laid out two perpendicular streets, the N-S cardo maximus and the E-W decumanus maximus, which divided the site into four sections of approximately equal size (centuriae). Streets of smaller width (cardines-decumani) lying parallel to the main streets delimited the building blocks themselves. The buildings associated with the political Agora (i.e., the Forum) were normally at the intersection of the two main streets.