Dasht-e Kavir
By the late Middle Ages, the term lost its administrative significance, in the west only being loosely applied among the Turko-Persian dynasties of modern Iran to all its territories that lay east and north-east of the Dasht-e Kavir desert. It was therefore subjected to constant change, as the size of their empires changed. In the east, "Khwarasan" likewise became a term associated with the great urban centers of Central Asia. It is mentioned in the Memoirs of Babur that: