The site covers 15 ha within its ramparts. There are two main building complexes: (i) to the north, the "Maison carrée" (see seminar); (ii) occupying much of the central-western area, a group of four buildings, each with a monumental façade overlooking a vast esplanade: the Bâtiment nord-est, the Salle carrée, the Bâtiment-tour and the Édifice rouge. Adjacent to the south is the Round Hall. We now know that all the buildings in this complex were built one after the other as part of a single overall design, with the exception of the Red Building, which initially stood alone. There are earlier buildings, but there is no archaeological confirmation that they date from before the time of Mithridates I.
Any consideration of New Nisa as a whole must take into account two facts: there were no other monumental buildings (the rest of the intramural space was occupied by ponds, warehouses and cellars) and there was no residential area either (the only premises intended for this purpose, very modest in scale, adjoined the Northeast Building). The material used was raw earth (bricks and adobe blocks). The use of building stone is very rare, limited to the bases of columns, which have been reused ever since. This exclusion is clearly an architectural choice, not a technical constraint, since there were good quarries nearby.
