B?b Al-Abw?b
B?B AL-ABW?B
B?B AL-ABW?B ("Gate of the Gates"; Persian Darband ; modern *Derbent ), a pass and town at the eastern end of the Caucasus range, where the road narrows between the mountains and the Caspian Sea. B?b al-Abw?b is mentioned in both the "Letter of ?asdai" and the "Reply of King Joseph" (see *Khazars), in the latter specifically as marking the southern limit of the Khazar domain. This agrees in general with the accounts of the Arabic geographers and historians. The latter described B?b al-Abw?b as guarding one of the two main passes of the Caucasus through which the Khazars invaded the lands of Islam. Extensive arrangements for the defense of B?b al-Abw?b are reported by the geographer al-I??akhr? (tenth century). Previously, the town had more than once been overrun from the north, though the successful Khazar attack against Ardabil (apparently in 730), referred to in the "Reply of King Joseph," was made via Dariel (now Daryal).
bibliography:
Dunlop, Khazars, index; Dunlop, in: eis2 (incl. bibl.); al-I??akhr?, Kit?b al-Mas?lik wa-al-Mam?lik (1961), 109–10; M. Artamonov, Istoriya Khazar (1962), index.
[Douglas Morton Dunlop]