The Bittern Desert is an arid area in the northeastern part of Atainia, Tysan. The desert was the site of a First Age battle between the great drakes and the Seardluin, resulting in its permanent destruction by dragonfire. The coastal area features anviled, rocky ridges backed inland by dry gulches and scrub thorn.
The port city of Lorn can be found in the desert, on the coast of the Instrell Bay, and a trade road connects the city to Isaer in the south. Althain Tower is situated on the southern border of the Bittern Desert, and an unnamed range of mountains rises to the west.