That this route, through the Korokh valley and across the water-parting by the Zirmast Pass to Naratu, was the high road between Herat and Balkh I have very little doubt. It was the route selected for mail service during the winter when the Afghan Boundary Commission camp was at Bala Murghab, on the Murghab River, and it was seldom closed by snow, although the Zirmast heights rise to over 7000 feet, and the Tir Band-i-Turkistan (which represents the northern _rebord_ or revetment of the uplands which contain the Murghab drainage) cannot be much less. The intense bitterness of a Northern Afghan winter is more or less spasmodic. It is only the dreaded shamshir (the "scimitar" of the north-west) which is dangerous, and travelling is possible at almost every season of the year. The condition of the mountain ways and passes immediately above Bala Murghab is not that of steep and difficult tracks across a rugged and rocky divide. In most cases it is possible to ride over them, or, indeed, off them, in almost any direction; but as these mountains extend eastward they alter the character of their crests. From Herat to Maruchak this is not, however, the direct road; the Kushk River, or the Kashan, offering a much easier line of approach.
All our investigations in 1884 tended to prove beyond dispute that Maruchak represents the famous old city of Merv-el-Rud, the "Merv of the River," to which every Arab geographer refers. Sir Henry Rawlinson sums up the position in the Royal Geographical Society's _Proceedings_ (vol. viii.), when he points out that there were two Mervs known to the ancient geographer. One is the well-known Russian capital in trans-Caspia, the "Merv of the Oasis," a city which, in conjunction with Herat and Balkh, formed the tripolis of primitive Aryan civilization. It was to this place that Orodis, the Parthian king, transported the Roman soldiers whom he had taken prisoners in his victory over Crassus, and here they seemed to have formed a flourishing colony.
Merv was in early ages a Christian city, and Christian congregations, both Jacobite and Nestorian, flourished at Merv from about A.D. 200 till the conquest of Persia by the Mahomedans. Merv the greater has as stirring a history as any in Asia, but Merv-el-Rud, which was 140 miles south of the older Merv, is altogether of later date. This city is said to have been built by architects from Babylonia in the fifth century A.D., and was flourishing at the time of the Arab invasion. All this Oxus region (Tokharistan) was then held by a race of Skytho-Aryans (white Huns) called Tokhari or Kushan, and their capital, Talikhan, was not far from Maruchak. Now, Merv-el-Rud is the only great city named in history on the Upper Murghab, above Panjdeh, before the end of the fourteenth century A.D. After that date, in the time of Shah Rokh (Timur's son), the name Merv-el-Rud disappears, and Maruchak takes its place in all geographical works, the inference being that, Merv-el-Rud being destroyed in Timur's wars, Maruchak was built in its immediate neighbourhood. This surmise of Rawlinson's is confirmed by the appearance of Maruchak, which is but an insignificant collection of inferior buildings surrounded by a mud wall, with a labyrinth of deep canal cuttings in front of it and a rough irregular stretch of untilled country around. Merv-el-Rud must have been a much greater place.