unnavigable

adj

1. Not navigable: difficult or impossible to navigate.

   “Near-synonym: impassible”

   “unnavigable website”

2. Not navigable: difficult or impossible to navigate.

   “A road journey of 70 miles past unnavigable rapids leads to Juba, from which it is seven days' steaming down river through to Kosti, on the Sudan Railways.”

   “Nang county is the name given to the present administrative division of E Dakpo, the principal gateway to the sacred mountain of Tsari, and the region through which the Brahmaputra River cuts its way through an unnavigable 33 km horse-shoe gorge as it flows towards Longpo and Kongpo.”

   “The vast plateau of the Massif Central was still the fortress it had been when the Arverni tribes held out against the Romans. Its rivers were unnavigable and its links to the rest of France practically non-existent.”

3. Not navigable: difficult or impossible to navigate.

   “The trail was unnavigable since the flood washed it away.”