impassable
US /ɪmˈpæs.ə.bəl/
UK /ɪmˈpæs.ə.bəl/

1.
impraticable, infranchissable
impossible to travel across or along
:
•
The road was rendered impassable by the heavy snowfall.
La route est devenue impraticable à cause des fortes chutes de neige.
•
The dense jungle made the terrain almost impassable.
La jungle dense rendait le terrain presque impraticable.