Columbia subject headings:
Mineral industries--Germany--Laacher Lake Region--History.
Rhineland-Palatinate (Germany)--Antiquities, Roman.
Romans--Germany--Rhineland-Palatinate.
Harvard subject headings:
Excavations (Archaeology)--Germany--Laacher Lake Region.
Human settlements--Germany--Laacher Lake Region--History.
Laacher Lake Region (Germany)--Antiquities, Roman.
Romans--Germany--Laacher Lake Region.
Volcanoes--Germany--Laacher Lake Region--History.
Princeton subject headings: