e.g. If:
1 = Emp + Nobles
2 = Clergy
3 = Lower Nobles/Rich Middle Class
4/5 = Middle Class and Rich craftsmen and people with a trade in the city, trading district.
6 = Rich Lower Class
7 = general lower class
8 = Industrial area, the workforce for that.
9 = s***** slums under the wall
Then:
Fugly Industrial District = Industrial Area = 8.
Grain Granary.. dunno, probably 5 so it's near the warehouses where the stuff comes in.
Brandeburg Gate thing: Where inner city walls meet a major road near the higher parts of the city. 5-3?
Cathedral: 2 but on a hill?
Citadel: Technically 1 but on a large outcrop dominating the city?
Town Square: Anywhere which is relatively prosperous.