Boquillas Canyon is a canyon in the Big Bend National Park. The canyon walls are 1,500 ft high and carved out of thick layers of limestone. The canyon length is a matter of some debate, with estimates ranging from 5 miles to 17 miles, depending on the chosen endpoint. The Rio Grande river currents through the canyon are rated up to Class II.
Boquillas means "little mouths" in Spanish, perhaps a reference to the canyon's narrow mouth.