ADEN, seaport and territory in Arabia, situated in 12° 45' N., and 45° 4' E., on a peninsula near the entrance to the Red sea, loom. east of the Strait of Bab-el-Mandeb. The peninsula of Aden has barren and desolate volcanic rocks, rising to 1776ft. and extending 5m. from east to west, and 3m. from its northern shore to Ras Sanailah or Cape Aden, its most southerly point ; it is con nected with the mainland by a neck of low sandy ground. The town is built on the eastern coast, in what is probably the crater of an extinct volcano, and is surrounded by precipitous rocks forming an admirable natural defence. There are two harbours, an outer, facing the town, protected by the island of Sirah, but now par tially choked with mud; and an inner, called Aden Back-bay, or, by the Arabs, Bandar Tawayih, on the western side of the penin sula, which at all periods of the year admits vessels drawing less than 20 feet. Aden suffers considerably from the want of good water, and the beat is often intense. A little water is obtained from wells, and some from an aqueduct 7m. long, built in 1867.
Aden early became the chief entrepot of trade between Europe and Asia. It is the 'Apal3ta of the Periplus. It was known to the Romans as Arabia Felix and Attanae, and was captured by them, probably in the year 24 B.C. In 1513 it was unsuccessfully attacked by the Portuguese under Albuquerque, but subsequently fell into the hands of the Turks in 1538. In the following century the Turks themselves relinquished their conquests in Yemen, and the sultan of Sana established a supremacy over Aden, which was maintained until 1735, when the sheikh of Lahej, throwing off his allegiance, founded a line of independent sultans.
From the 16th to the 19th century traffic between Europe and the East had mostly gone via the Cape of Good Hope. The an nexation of Aden to British India in 1839 renewed trade between India and the Red sea and this developed enormously after the cutting of the Suez canal. Aden was made a free port and a coal ing station and its territory has been extended by cession or pur chase. The island of Perim in the Strait of Bab-el-Mandeb was occupied in 1857. In addition to its east and west trade Aden has many commercial relations with the intefior and with the coast of Africa opposite.
The chief imports are coffee, cotton-piece goods, grain, bides, coal, sugar and tobacco. The exports are, in the main, the same as the imports. Aden itself produces salt and cigarettes. The trade is largely a transhipment trade. In 1925-26 the total value of im ports was Rs.8,98,19,456, of which Rs.28,20,66o was land-borne; and of exports Rs.7,52,67,613, of which Rs.29,00,581 was land borne, as compared with imports valued at Rs.6,56,62,23o and ex ports at in 1913-14. In 1925-26, 1,315 merchant vessels of 4,356,326 tons (net) entered the port of Aden besides 1,029 local craft. The submarine cables of the Eastern Telegraph Company here diverge—on the one hand to India, the Far East and Australia, and on the other hand to Zanzibar and the Cape. During the war of 1914-18 a metre-gauge railway was constructed for military purposes from Aden to Lahej, 26 miles. Later it was extended to Habil, a further eight miles. The total population of the settlement in 1921 including Perim island was 54,923 (includ ing about 500 Europeans) as compared with less than 1,000 in 1839. The nonulation fell to 48,338 in Boundaries and Administration.—The frontier of the pro tectorate was demarcated in 1902-04, and in 1905 a convention was signed by the British and Ottoman commissioners determin ing the boundary from Sheikh Murad on the Red sea coast to the Bana river, and thence in a north-easterly direction into the desert. By an Anglo-Turkish Convention of 1914 the boundary was pro longed to a point on the shores of the Persian gulf opposite Bah rein island. During the World War, the Turkish forces encroached on Aden territory and approached to within a short distance of the town ; they occupied Lahej and Sheikh Othman. At the end of the war the Turks withdrew from the Yemen. The neighbouring ter ritories of the Iman of San'a conform, theoretically, with the 1905 line, though encroachments had been made at some points which, in 1925, were the subject of dispute.
Previously part of the Bombay Presidency, Aden became a sep arate province in 1932, with a Chief Commissioner responsible to the Indian Government. The relations of Aden with the iest of Arabia and with the tribes of the protectorate were taken charge of during the World War by the high commissioner of Egypt. In 1920 political control was transferred to the political resident, who was directly responsible to the British Foreign Office. In 1921 this responsibility was taken over by the Colonial Office. It was further agreed that for the future London should be responsible for the political and military administration, the Government of India remaining responsible for the internal administration. A Draft Order-in-Council published on July 7, 1936, provided that Aden should on April 1, 1937, cease to be part of British India and become a Colony under a Governor and Commander-in-Chief. The territory was thus transferred from Indian to Imperial control.