The Isthmus of Xana is a strip of land that wraps around the eastern coast of the inland Dreki Sea, and separates it from the Estrill Ocean to the east. The Isthmus was originally part of the Kingdom of Reinhart, but after the chaos that erupted in the years after Wulf XIII's death, the area became a patchwork of micro-nations that were an easy target for the Hobgoblin Legions of Korinthos who now inhabit the area.
The area of the Isthmus of Xana is incredibly fertile land, and much of it has been turned into farmland by the Korinthian state. The south of the Isthmus has been turned over to pasture lands rather than arable farming, and there are several large areas of heavily managed woodlands, not originally native to the area, planted by the Hobgoblins to provide lumber. Near the border with the Kingdom of Sharisar to the south, the land turns from being mostly flat to a landscape of gently rolling hills.
The north of the Isthmus is substantially drier and less fertile than the rest of the area, and a forest of spiny scrubland acts as a natural border between Korinthos and the patchwork of the Mountain Principalities beyond.