From GOD'S WAR:
Nyx woke just before dawn, as the call of the muezzin to dawn prayer sounded across Dadfar. The city pooled at the edge of the desert sea just northwest of the mining town of Zikiri in the Chenjan interior. When the wind blew the wrong way, Dadfar got misted over in a fine haze of toxic grit. The city used to sit along a broad river, maybe a thousand years before, but the river was gone now, and the sand had swallowed any record of it.