The Collaborative International Dictionary of English v.0.48:

Farness \Far"ness\, n. [From Far, a.]
   The state of being far off; distance; remoteness. [R.]
   --Grew.
   [1913 Webster]

WordNet (r) 3.0 (2006):

farness
    n 1: the property of being remote [syn: farness, remoteness,
         farawayness] [ant: closeness, nearness]