Title: Piedras Negras archaeology, 1931-1939
Subjects: Antiquities, Archaeological expeditions, Excavations (Archaeology), History, Maya architecture, Maya sculpture, Social Science, Archaeology / Anthropology, Usumacinta River Valley (Guate, Sociology, Archaeology, Usumacinta River Valley (Guatemala and Mexico), Mayas, antiquities
Places: Piedras Negras Site (Guatemala), Usumacinta River Valley (Guatemala and Mexico)