Synonyms of unexplored

2 Syllables
unknown, foreign
3 Syllables
so-and-so, such-and-such, unmapped, uncharted, unplumbed
4 Syllables
unfamiliar, unexplained, untraveled, unperceived, romanesque, unfathomed, extralocal, nonnative, nonresident, non-resident, undetected, unexposed
5 Syllables
undiscovered, unapprehended, unascertained, undetermined
6 Syllables
uninvestigated