Chittagong ( CHIT-ə-gong), officially Chattogram (Bengali: চট্টগ্রাম, romanized: Côṭṭôgrām, IPA: [ˈt͡ʃɔʈːoɡram] , traditionally Bengali: চাটগাঁও, romanized: Cāṭgão; Chittagonian: চিটাং/সিটাং, romanized: Sitang), is the second-largest city in Bangladesh. Home to the Port of Chittagong, it is the busiest port in Bangladesh and the Bay of Bengal. The city is also the business capital of Bangladesh. It is the administrative seat of an eponymous division and district. The city is located on the banks of the Karnaphuli River between the Chittagong Hill Tracts and the Bay of Bengal. In 2022, the Chittagong District had a population of approximately 9.2 million according to a census conducted by the government of Bangladesh. In 2022, the city area had a population of more than 5.6 million. The city is home to many large local businesses and plays an important role in the Bangladeshi economy.
One of the world's oldest ports with a functional natural harbor for centuries, Chittagong appeared on ancient Greek and Roman maps, including on Ptolemy's world map. It was located on the southern branch of the Silk Road. In the 9th century, merchants from the Abbasid Caliphate established a trading post in Chittagong. The port fell to the Muslim conquest of Bengal during the 14th century. It was the site of a royal mint under the Delhi Sultanate, Bengal Sultanate and Mughal Empire. Between the 15th and 17th centuries, Chittagong was also a centre of administrative, literary, commercial and maritime activities in Arakan, a narrow strip of land along the eastern coast of the Bay of Bengal which was under strong Bengali influence for 350 years. During the 16th century, the port became a Portuguese trading post and João de Barros described it as "the most famous and wealthy city of the Kingdom of Bengal". The Mughal Empire expelled the Portuguese and Arakanese in 1666.
