But apart from these two roads, scarcely anything whatever is known of the country. Especially the mountainous region of Rhodopê, bounded on the west by the Strymon, on the north and east by the Hebrus, and on the south by the Ægean, is a Terra Incognita, except the few Grecian colonies on the coast. Very few travellers have passed along, or described the southern or King’s Road, while the region in the interior, apart from the high road, was absolutely unexplored until the visit of M. Viquesnel in 1847, under scientific mission from the French government. The brief, but interesting account, composed by M. Viquesnel, of this rugged and impracticable district, is contained in the “Archives des Missions Scientifiques et Litteraires”, for 1850, published at Paris. Unfortunately, the map intended to accompany that account has not yet been prepared; but the published data, as far as they go, have been employed by Kiepert in constructing his recent map of Turkey in Europe; the best map of these regions now existing, though still very imperfect. The Illustrations (Erläuterungen) annexed by Kiepert to his map of Turkey, show the defective data on which the chartography of this country is founded. Until the survey of M. Viquesnel, the higher part of the course of the Strymon, and nearly all the course of the Nestus, may be said to have been wholly unknown. The terror spread by Alexander’s military operations was so great, that not only the Triballi, but the other autonomous Thracians around, sent envoys tendering presents or tribute, and soliciting peace. Alexander granted their request. His mind being bent upon war with Asia, he was satisfied with having intimidated these tribes so as to deter them from rising during his absence. What conditions he imposed, we do not know, but he accepted the presents.[62] [62] Arrian, i. 4, 5; Strabo, vii. p. 301.