Pongo (geography) explained

A pongo is a word used in the Peruvian Spanish dialect for 'canyon'. It is derived from either Quechua puncu or the Aymara ponco, meaning 'door' or 'gate.'

See:

• The Pongo de Manseriche: a gorge in northwest Peru where the Marañón River runs. The Marañón River has 35 miles of pongo before it joins the Amazon River.
• The Pongo de Mainique: the most dangerous whitewater pass on the Urubamba River.
• The Huallaga River forms the when crossing a part of the Andes.

References

• Church . George Earl . Amazon . 1. 786–789.