Columbia subject headings:
Harvard subject headings:
Architecture--Arid regions--Saudi Arabia.
Cave architecture--Saudi Arabia--Madāʾin Ṣāliḥ.
Hejaz Railway--Pictorial works.
Madāʼin Ṣāliḥ (Saudi Arabia)--Antiquities.
Madāʼin Ṣāliḥ (Saudi Arabia)--Description and travel.
Monuments--Saudi Arabia--Madāʾin Ṣāliḥ.
Petroglyphs--Saudi Arabia--Madāʾin Ṣāliḥ.
Saudi Arabia--Antiquities.
Saudi Arabia--Description and travel.
Princeton subject headings:
Architecture, Nabataean--Saudi Arabia.
Architecture--Arid regions--Saudi Arabia.
Cave architecture--Saudi Arabia.
Hejaz Railway--Pictorial works.
Madāʼin Ṣāliḥ (Saudi Arabia)--Antiquities.
Madāʼin Ṣāliḥ (Saudi Arabia)--Pictorial works.
Nabataeans.
Saudi Arabia--Antiquities.
ʻUlā (Saudi Arabia)--Pictorial works.