Columbia subject headings:
Harvard subject headings:
Roads, Roman--Congresses.
Roads--Maintenance and repair--Congresses.
Rome--Antiquities--Congresses.
Water-pipes--Rome--Congresses.
Water-supply--Rome--Congresses.
Princeton subject headings:
Roads, Roman--Congresses.
Roads--Maintenance and repair--Congresses.
Rome--Antiquities--Congresses.
Water-pipes--Rome--Congresses.
Water-supply--Rome--Congresses.