One of the characteristicss of Bangladesh is that its relief is realtively flat. The result is that it suffers from frequent floods during the monsoon season (June to October), when all of the rivers that descend the Himalayas and Tibetan plateau flow into the Bay of Bengal. Three major rivers traverse the country: the Ganges, the Brahmaputra and the Meghna, creating a mountainous and waterlogged 579 million miČ basin. However, rerouted by the Himalayas, they all flow into the Bay of Bengal. Being an ultra-flat country 12 times smaller than Bangladesh, this explains the many floods.
Essentially consisting of silt, Bangladesh has a very particular geography. Because of its flat relief and frequent floods, islands of silt, as unstable as they are fertile, are regularly formed. The locals, who do not have much land, quickly take root on these islands, cultivate them and then live on them. This is thus how a huge mangrove swamp (the largest in the world) has been created, becoming a refuge for human beings and many types of plant and animal species.
Mainly composed of fertile plains, although there are a few hilly areas, Bangladesh is best discovered by boat via the numerous rivers that feed the country.