On Yuan Chwang's Travels in India, 629–645 A.D. v2.c26.s1.30

v2.c26.s1.30

While staying at Samarkand, Yuan-chwang collected and recorded much information concerning neighbouring regions, and then continued his march, in a direction slightly west of south, to Shahr-i-sabz in Kesh (K'a-sha, K'ê-shih, or Kasanna). From this town he proceeded, by four marches, a distance of about 55 English miles, nearly due south to the famous defile of the ‘Iron Gates’, which marked the boundary between Sogdiana and Tokhāristān (Tu-ho-lo, Bactria), and is situated about eight miles to the west of Derbent (N. lat. 38° 11', E. long. 66° 54').¹ Yuan-chwang thus attained the most westerly point of his pilgrimage, having traversed about forty-two degrees of longitude since he quitted the Chinese capital.