Most of the areas of Bangladesh lies within the broad delta formed by the Ganges and Brahmaputra rivers. Lands are exceedingly flat, low-lying, and subject to annual flooding. Much fertile, alluvial soil is deposited by the floodwaters. The only significant area of hilly terrain, constituting less than one-tenth of the nation's territory, is the Chittagong Hill Tracts in the narrow southeastern panhandle of the country.
Dhaka is the capital and largest city of Bangladesh. Today's Dhaka has a long story of evolution. It was founded during the 10th century. It served as the Mughal capital of Bengal from 1608 to 1704.Before coming under British rule in 1765 it was a trading center for British, French, and Dutch colonialism . In 1905 it was again named the capital of Bengal, and in 1956 it became the capital of East Pakistan. During the Bangladesh war of independence in1971 the city suffered a heavy damage. In 1982 the spelling was changed from ' Dacca' to 'Dhaka'.