Eberron - Return of the Lich Queen
Khorvaire is found in Eberron’s northern hemisphere. It is bounded by the Bitter Sea to the north, the Lhazaar Sea to the east, the Barren Sea to the west and the Thunder Sea to the south.
The landscape of Khorvaire varies greatly, from wastelands and forbidding mountains in the north to deserts and jungles in the south, with everything in between.
For more information: Eberron Wiki