Certain Common Features of the Ancient Cities Walls : primarily for military defense but also to emphasize the separation of the urban community from the countryside. They contained a market but it was not in the city centre like modern cities. The main buildings were nearly always religious or political such as temples, palaces or courts. The dwellings of the ruling class or elite tended to be concentrated in or near the centre while the less privileged lived near the edges. The places of work and residence were the same.