The Collaborative International Dictionary of English v.0.48:

Unfortified \Unfortified\
   See fortified.

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "unfortified":
   absolute, bare, bare-handed, clarified, clear, defenseless,
   distilled, guardless, helpless, naked, neat, purified, rectified,
   sheer, straight, unadulterated, unalloyed, unarmed, unarmored,
   unattended, unblended, uncombined, uncompounded, uncorrupted,
   uncovered, undefended, undiluted, ungarrisoned, unguarded,
   unleavened, unmingled, unmixed, unprotected, unscreened,
   unsheltered, unshielded, unsophisticated, unsuspecting, untinged,
   unwarned, unwatched, weaponless