unchartered, unexplored, terra incognita, unmapped, untrodden, untested, murkiest, perilous, unfamiliar, unfathomed, undiscovered, unnavigable, twilight zone, unimagined, treacherous, untraveled, unknown, headlong, untamed, unsurveyed, inhospitable, pathless, untried, untouched, uninhabited, rocky, bermuda triangle, unstudied, illimitable, inaccessible, untapped, comfort zone, dicey, desolate, unknowable, fertile, ungoverned, undreamed, adventurous, subpolar, rabbit hole, untethered, unpopulated, unexploited, explorable, esoteric, interplanetary, subaquatic, roiling, icebound, interstellar space, circuitous, bumpy, antarctic, chthonic, unclimbable, unknown quantity, deep, swampy, risky, unexamined, unpredictable, rarified, rarefied, moonlike, obscure, uncertain, prehistoric, unproven, unfathomable, drake passage, abyssal, unconquered, unsolvable, turbulent, barren, trackless, subterranean, unreachable, undefined, twilit, unpredicted, unseen, unforgiving, unsettled, unregulated, intrepid, daunting, biogeographical, icy, cryptozoological, muddy, unmined, unpassable, unthought, glacial, conquerable, evolutional, trammeled, unplumbed, unprotected, unploughed, unpeopled, swept, unfrequented, charted, uninhabitable, mountainous, untracked, waterless, roadless

chartless