RICE, was Toponyms

The SF writer Jack Vance has written stories of the future which take
place in "The Gaean Reach" as well as an earlier non-series story "To
Live Forever," about the stresses of a society in which immortality can
be earned. This characters of this story live in the "Reach of Clarges."
These are the only examples known to me this AM of the use of 'reach' in
this sense. (I admit to not having an OED handy.)

The Gaean Reach is a continuation of his earlier fictional milieu, the
"Oikumene,"  that part of the Galaxy colonized and inhabited by humans.

--John