  We study the worldsheet CFTs of type II strings on compact $G_2$ orbifolds
obtained as quotients of a product of a Calabi-Yau threefold and a circle. For
such models, we argue that the Calabi-Yau mirror map implies a mirror map for
the associated $G_2$ varieties by examining how anti-holomorphic involutions
behave under Calabi-Yau mirror symmetry. The mirror geometries identified by
the worldsheet CFT are consistent with earlier proposals for twisted connected
sum $G_2$ manifolds.
