Boquillas Canyon is a limestone canyon in Big Bend National Park in far West Texas, where the Rio Grande has cut a deep passage through the border landscape. Its steep walls rise about 1,500 feet, making it one of the park’s most dramatic river corridors. The canyon’s reported length varies from about 5 to 17 miles depending on where it is measured. On the river, Class II currents create a stretch that is relatively mild yet still active for paddling. Derived from Spanish for “little mouths,” its name likely refers to the canyon’s narrow entrance and its striking enclosed setting.