The Wheel of Time - The Call of the Horn
The Great Rift is an immense rip in the world’s surface, a large canyon which marks the eastern edge of the Aiel Waste and the western border of Shara. The Great Rift runs south and east from the Cliffs of Dawn for over 450 leagues (1,800 miles) before petering out in the vicinity of the Sea of Storms. Immense mountains are located east of the Rift, further hindering travel into Shara. Also, the southern-most extent of the Rift is located east of the desert known as the Termool.
The rift ranges in depth from one to three miles (5,280 to 15,840 feet). There are no known settlements along the rift.