The caravans travelled far beyond the limits of the empire.
But while the province in many parts presents a landscape of luxuriant beauty, it is a prey to the ravages of disease, principally malarial fevers due to the extensive swamps formed by waters stagnating in the forests, and to the frequent incursions of the Goklan and Yomut Turkomans, who have their camping-grounds in the northern part of the province, and until about 1890 plundered caravans sometimes at the very gates of Astarabad city, and carried people off into slavery and bondage.
Of Asia, and were brought, through Russian caravans, even so far as to Pomerania, Sweden and Norway, where Samanid coins have been found in great number, were in their turn overthrown by a more youthful and vigorous race, that of Sabuktagin, which founded the illustrious Ghaznevid dynasty and the Mussulman empire of India.
There is reason to believe that before the 6th century B.C. the caravans reached Damascus without coming near the oasis of Tadmor; probably, therefore, we may connect the origin of the city with the gradual forward movement of the nomad Arabs which followed on the overthrow of the ancient nationalities of Syria by the Babylonian Empire (6th century B.C.).
Originally an Arab settlement, the oasis was transformed in the course of time from a mere halting-place for caravans to a city of the first rank.