city that is the chief Indian Ocean port of Bangladesh. It lies about 12 miles (19 km) north of the mouth of the Karnaphuli River, in the southeastern arm of the country. It is a major communications centre and is linked by rail and road with Dhaka, Comilla, and Feni (all to the northeast) and by air with Dhaka, Cox's Bazar (to the southwest), and several international destinations, including Kolkata (Calcutta) (Calcutta; in India), Muscat (in Oman), and Dubai (in the United Arab Emirates). Among the most important industrial cities in Bangladesh, Chittagong has various manufacturing establishments that extend about 10 miles (16 km) to the north and northeast from the city proper.

The area surrounding Chittagong is heavily populated and comprises a narrow strip of coast along the Bay of Bengal (Bengal, Bay of) and ranges of low hills separated by fertile valleys. The climate is moist, warm, and equable, with a heavy rainfall amounting to more than 100 inches (2,540 mm) annually, falling mainly during the summer monsoons. The area's chief rivers are the Karnaphuli (Karnaphuli River), Feni, Halda, Sangu, and Matamuhari. The higher parts of the Chittagong Hills are forested, while the lower portions are covered predominantly with brushwood. Between the hills lie cultivated valleys that were originally filled by deposits of sand and clay washed down from the hills. Rice is the most important crop; tea is grown on low hills that are unfit for rice cultivation. Chilies and vegetables are also grown, and cane and bamboo are economically valuable forest products.

Chittagong's fine natural harbour was known to the Mediterranean world from the early Common Era and to Arab sailors by the 10th century. It was called Porto Grande by Portuguese and Venetian voyagers and was described by João de Barros (Barros, João de) in 1552 as “the most famous and wealthy city of the Kingdom of Bengal.” It has been generally identified with the city of Bengala described by early Portuguese and other writers. Conquered by the Muslims in the 14th century, Chittagong passed to the Arakanese in the next century. The piratical raids of the Arakanese and their Portuguese mercenaries led to the dispatch of a strong force by Shaista Khan, the Mughal (Mughal Dynasty) governor (nawab) of Bengal, who in 1666 occupied the region. Chittagong was ceded to the British East India Company in 1760.

Chittagong was constituted a municipality in 1864 and has grown in different directions along the main routes of transportation. Although the headquarters of the Bangladesh Railway are in Chittagong, and the railway workshop is in the nearby town of Pahartali, the port has remained the centre of city life and trade. After the creation of Pakistan in 1947, much trade was diverted to Chittagong from Calcutta, and the port was improved considerably. With well-equipped facilities and numerous permanent jetties and moorings, the port has become the gateway of Bangladesh for foreign trade. The city has an export-processing zone as well as branch offices of many foreign firms and banks.

Chittagong was developed according to a series of master plans, which included the construction of various buildings and two sizable markets (covering an area of about 700,000 square feet 【65,000 square metres】). Cotton and jute milling, tea and match manufacturing, chemical production, and engineering works are among the principal industries. Along with jute and jute manufactures, tea and naphtha are among the city's principal exports. An iron and steel mill and a large oil refinery also are located in the city, and a large-capacity pipeline links the oil refinery with an offshore terminal.

Chittagong has several hospitals, an ethnological museum, and many institutions of higher education, of which the University of Chittagong (1966) and Chittagong University of Engineering and Technology (1968) are the most prominent. Nearby are a cadet college (at Faujdar Hat) and a merchant-marine academy. Pop. (2001) 2,202,637.