Synonyms of the word 
UNTRAVERSABLE → IMPASSABLE - UNPASSABLE
untraversable
- adj. That cannot be traversed.
impassable
- adj. (of a route, terrain, etc.) Incapable of being passed over, crossed, or negotiated.
- adj. (of an obstacle) Incapable of being overcome or surmounted.
- adj. (of currency) Not useable as legal tender.
unpassable
- adj. Not able to be passed.
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