Baku, an important seaport of Russian Transcaucasia, on the Apsheron peninsula, on a crescent-shaped bay in the Caspian Sea. Since 1883 it has been connected by rail with Tiflis, and so with Poti and Batoum on the Black Sea, 561 miles distant; and since 1887, by the North Caucasus Railway, with Novorossiak on the Black Sea. The whole soil around Baku is impregnated with petroleum, which, monopolised till 1872, now forms the staple branch of its industry. Some of the fountains ignite spontaneously, a fact which caused Baku to be esteemed as a holy city by the Parsees (see Ateshga). Most of the petroleum wells are situated on the Balakhani peninsula, 8 or 9 miles to the north. Lines of pipe carry the oil into the ' black town' of Baku, which is full of oil refineries emitting vast volumes of smoke. One well, tapped in 1886, began to spout oil with extraordinary force, deluging the whole district, till the outflow, on the eighth day, had reached a daily rate of 11,000 tuns, or more than the entire produce of the world at the time. Another gigantic naphtha fountain burst out in 1887, rising to a height of 350 feet, and after forming an extensive petroleum lake, forced its way into the sea. How rapidly the industry grew may be judged from the fact that the number of drilled wells increased from 1 in 1871 to 400 in 1883. Cotton, silk, opium, saffron, and salt are also exported. The Arabian Masudi is the first who mentions Baku, about 943, and he gives an account of a great volcanic mountain in its vicinity, now extinct. Baku was taken by Russia from the Persians in 1806. The harbour, which is strongly fortified, is one of the chief stations of the Russian navy in the Caspian. The population - some 16,000 in 1880 - was in 1900 about 115,000. Baku is capital of a government of Russian Transcaucasia, with an area of 15,516 sq. m., and a pop. of 810,000. See works by Marvin (1884-86).