Formerly known as Dacca, is the capital and largest city of Bangladesh. It's one if the largest and most densely populated cities in the world, with a population of 18.89 million people in the Greater Dhaka area.
I did some research and found that Dhaka, also spelled Dacca, city and capital of Bangladesh. It is located just north of the Buriganga River, a channel of the Dhaleswari. Also, it is one of the most populous cities in the world.
Also, Sylhet is a city in eastern Bangladesh, <em>not</em><em> </em>the capital, and Jamalpur is a town in <em>India</em><em> </em>in the state of Bihar.