Synonyms of unsurmountable

Adjective

1. insurmountable (vs. surmountable), unsurmountable, insuperable, unconquerable, impossible, unconquerable

usage: not capable of being surmounted or overcome; "insurmountable disadvantages"

2. unsurmountable, unclimbable, impassable (vs. passable), unpassable

usage: incapable of being surmounted or climbed