Columbia subject headings:
Archaeology, Medieval--Spain--Esla River Valley.
Cave architecture--Spain--Esla River Valley.
Earth sheltered houses--Spain--Esla River Valley.
Underground architecture--Spain--Esla River Valley.
Vernacular architecture--Spain--Esla River Valley.
Harvard subject headings:
Archaeology, Medieval--Spain--Esla River Valley.
Architecture, Medieval--Spain--Esla River Valley.
Cave architecture--Spain--Esla River Valley.
Earth sheltered houses--Spain--Esla River Valley.
Excavations (Archaeology)--Spain--Esla River Valley.
Underground architecture--Spain--Esla River Valley.
Vernacular architecture--Spain--Esla River Valley.
Princeton subject headings:
Archaeology, Medieval--Spain--Elsa River Valley.
Cave architecture--Spain--Esla River Valley.
Earth sheltered houses--Spain--Esla River Valley.
Underground architecture--Spain--Elsa River Valley.
Vernacular architecture--Spain--Esla River Valley.