Siberia

Siberia stretches before them as a vast, unforgiving expanse, its reputation as a remote corner of confinement heavy in Hayter's mistaken reference. The cold is oppressive, but more than the temperature, it's the association—the place held frozen behind geopolitical walls, where enemies of the state vanish into obscurity. The terrain here isn't described by snow or pine; it's defined by absence: the absence of escape, the absence of witnesses, the absence of time itself. Hayter's slip reveals a mental landscape as well as a physical one, where the Doctor's logical explanations crumble against the weight of a phrase that carries centuries of dread. It is not a place anyone recognizes from geography, but from tales of forced labor and forgotten gulags.