The Sophine Hills is the outgrowth of Philosophia that has expended beyond the Pactwalls to its south. That which has grown outside the walls to the north is called the Peripherie.
The Sophine Sanitorium is much less dense than Philosophia itself and even the Peripherie, but still maintains a good view over and access to it. It reaches up into the hills, in which a number of castles, manors and estates are built. Most importantly perhaps though is the Sophine Sanitorium overseeing everything below - the exact one where the Sanitorium Empire itself was proclaimed and the main gathering place that the Philosophers and Knights of the Round gather.
Following the Sophine Hill’s road to the south leads into Imperial Mogxa, including the Imperial City that the Western Kobold Dynasty once sat in.