Columbia subject headings:
Architecture, Carolingian--Germany--Cologne.
Christian art and symbolism--Germany--Cologne--Medieval, 500-1500.
Excavations (Archaeology)--Germany--Cologne.
Kölner Dom.
Harvard subject headings:
Architecture, Carolingian--Germany--Cologne.
Christian art and symbolism--Medieval, 500-1500--Germany--Cologne.
Excavations (Archaeology)--Germany--Cologne.
Kölner Dom.
Princeton subject headings:
Architecture, Carolingian--Germany--Cologne.
Christian art and symbolism--Medieval, 500-1500--Germany--Cologne.
Excavations (Archaeology)--Germany--Cologne.
Kölner Dom.