  A string theory in $3$ euclidean spacetime dimensions is found to describe
the semiclassical behavior of a certain exact physical state of quantum general
relativity in $4$ dimensions. Both the worldsheet and the three dimensional
metric emerge as collective coordinates that describe a sector of the solution
space of quantum general relativity. Additional collective coordinates exist
which are interpreted as worldsheet degrees of freedom. The construction may be
extended to the case in which the Kalb-Ramond field is included in the
non-perturbative dynamics. It is possible that this mechanism is the inverse of
the strong coupling limit by which some $D$ dimensional string theories are
conjectured to give rise to $D+1$ dimensional field theories.
