The Chittagong Port () is the main seaport of Bangladesh. Located in Bangladesh's port city of Chittagong and on the banks of the Karnaphuli River, the port handles over 90 percent of Bangladesh's export-import trade, and has been used by India, Nepal and Bhutan for transshipment. According to Lloyd's, it ranked as the 58th busiest container port in the world in 2019. The port is one of the oldest in the world, with a recorded history dating back to ancient Roman accounts. It is the busiest container port on the Bay of Bengal. Congestion is a major challenge in Chittagong port. The port had a congestion rate of 84.3 hours between January and July in 2017. History The Chittagong area has been a recorded seaport since the 4th century BCE. In the 2nd century, the harbor appeared on Ptolemy's map, drawn by the Greco-Roman cartographer Claudius Ptolemy. The map mentions the harbor as one of the finest in the Eastern world. The Periplus of the Erythraean Sea documents trade between Chittagong and private merchants from Roman Egypt. Arab traders frequented Chittagong since the 9th century. In 1154, Al-Idrisi noted that merchants from Baghdad and Basra regularly travelled to Chittagong. Arab traders played an important role in spreading Islam in the region. The port appears in the travelogues of Chinese explorers Xuanzang and Ma Huan. The Moroccan explorer Ibn Battuta and the Venetian traveler Niccolo De Conti visited the port in the 14th century. The historical port had ship trade with Africa, Europe, China and Southeast Asia. The Portuguese settlement in Chittagong centered on the port in the 16th and 17th centuries. After the Portuguese were expelled, Chittagong came under the rule of the Mughal Empire and was named Islamabad. It became an important shipbuilding center, catering to the Mughal and Ottoman navies. After the rise of British dominance in Bengal following the Battle of Plassey and Battle of Buxar, the Nawab of Bengal ceded the port to the British East India Company in 1772. Modern The modern Chittagong port was organized in 1887 under the Port Commissioners Act in the British Indian Empire. The port began formal operations under a commissioner in 1888. Its busiest trade links were with British Burma, including the ports of Akyab and Rangoon; and other Bengali ports, including Calcutta, Dhaka and Narayanganj. In the year 1889–90 the port handled exports totalling 125,000 tons. The Strand