Balkh (the ancient kingdom of Bactria), a province of Central Asia, now a dependency of the khanat of Bokhara, lying between Lat. 35. and 37. N., and Long. 63. and 69. E. The country of Balk is bounded by the Oxus on the N., by the great mountain range of the Hindu Khoh and Paropamisus on the S., by Badakshan on the E., and generally by sandy deserts on the W. It is said to extend 250 miles from E. to W., and from 100 to 120 miles from N. to S. Towards the S. the country abounds in hills which branch out from the Hindu Khoh range. Here the soil is generally stony, though it has many well-watered valleys. The central portion of the country is level, fertile, and well watered, from the vicinity of the hills; while towards the N., near the stream of the Oxus, it is sandy and barren. The western part of the country of Balk, which borders on the desert, is of a similar nature; but in the E., there are mountainous tracts which are well watered, and occasionally fertile. The country descends very rapidly from the mountain range of Hindu Khoh, and towards the Oxus is of a lower level and of a much hotter climate than those parts of Afghanistan which lie to the S. of these mountains. Balk is inhabited by the Usbek-Tatars, Tajiks, and Arabs. The total population is estimated at 1,000,000.

Balch (the ancient Bactra), formerly a great city, is now an immense and desolate mass of ruins, situated on the right bank of the Adrissh, or Balk River, in a large and fertile plain, 1800 feet above the sea. These ruins consist chiefly of fallen mosques and decayed tombs built of sun-dried bricks, and occupy a space of about twenty miles in circuit. None of these ruins are of an age prior to Mahometanism. Balk is still called by the Asiatics "Mother of Cities," but its population, which once numbered some hundred thousands, now scarcely amounts to 2000. This city is said to have been built by Kaioumirs, the founder of the Persian monarchy; and here the archi-magus resided till the followers of Zoroaster were overcome by the khalifa. Zenghis Khan sacked the city, and butchered its inhabitants; and under the house of Timour it became a province of the Mogul empire. Balk formed the government of Aurungzebe in his youth, and was at last invaded by the great Nadir. Under the Dooranee monarchy it fell into the hands of the Afghans; and for the last twenty years it has been in the possession of the Khan of Bokhara. (See Burnes's Travels in Bokhara.)