Columbia subject headings:
Architecture, Roman--Spain--Mérida.
Mérida (Spain)--Antiquities.
Triumphal arches--Spain--Mérida.
Harvard subject headings:
Arch of Trajan (Mérida, Spain)
Architecture, Roman--Spain--Mérida.
Mérida (Spain)--Antiquities.
Mérida (Spain)--Buildings, structures, etc.
Triumphal arches--Spain--Mérida.
Princeton subject headings:
Arch of Trajan (Mérida, Spain)
Architecture, Roman--Spain--Mérida.
Mérida (Spain)--Antiquities.
Mérida (Spain)--Buildings, structures, etc.
Triumphal arches--Spain--Mérida.