The course of the Padma, as the main course of the Ganges is known in Bangladesh, changed considerably during the period 1600 to 2000 AD. It is difficult to trace accurately the various channels through which it flowed, but the probability is that it flowed past Rampur Boalia, through Chalan Beel, the Dhaleshwari and Buriganga rivers, past Dhaka into the Meghna estuary.