Outer Mongolia

Meanings

1. Mongolia; a region south of Siberia, west of Manchuria and north of Inner Mongolia (with closely related native Mongolian population), well north of the Great Wall, which never became an integral part of the Chinese empire, and later achieved autonomy and full independence of China, as the republic of Mongolia
2. Any proverbially distant or remote place.

Etymology

outer (exterior, seen from China proper) + Mongolia