Pongo (geography)
A pongo (corruption of the Kichwa punku and the Aymara punku, meaning a door) is a type of canyon or narrow gorge along rivers in Peru, especially on the Marañón River (Upper Amazon) and its affluents, in the Amazonas Region.
See:
Britannica, Encyclopædia, Eleventh Edition, Volume 1 (1911). "Amazon River". Project Gutenberg Encyclopedia.
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