Baikunthapur is a Terai forest region in the western part of the Dooars in West Bengal, India, south of the Himalayan foothills, between the Mahananda River to the west and Teesta River to the east. The main towns in the area are Siliguri and Jalpaiguri. The forests are partly in the Darjeeling district and partly in the Jalpaiguri district. Baikunthapur is an important ecological zone, home to many wild elephants, but is threatened by growth of the local population. The least disturbed areas are in the Mahananda Wildlife Sanctuary. Historically, the Baikunthapur forests were the secure base of the Raikat princes in the time when Koch Bihar was an independent kingdom. Geology and climate The northern part of West Bengal is covered by fans of sediment washed down from the Himalayas. The Baikanthapur formation is the youngest fan in the area. It consists of very fine white sand inter-layered with ochre yellow sticky silty clay and overlain by dark grey to thick silty loam. The Shangaon formation represents the deposits of the flood plain faces of the Baikunthapur formation. Measurements have shown a maximum arsenic content well beyond the permissible limit (0.05 mg/L, Indian standard) within a depth range of 10–30m, in the Shaugaon surface. This raises concerns about the possibility of arsenic poisoning in the region and in downstream locations. There are three main seasons: summer, monsoons and winter. The summer season extends from the first week of March to the second week of June, with April being the hottest month. Summer temperatures range in the mid-30s C. The monsoons (June and September) bring severe rain. 125 mm or more may fall in 24 hours, bringing all activity to halt and often causing local floods and landslides. Annual rainfall may exceed 250 cm. Winters (September–February) can be chilly, with cold winds from the Himalayas. Temperatures may fall as low as 5 °C during this period. The land use pattern has changed dramatically since discovery of the potential for growing tea and reduction of the incidence of malaria. At one time, the area was one of dense forests, lakes and marshes laced with constantly shifting rivers. In the last fifty years, a huge influx of people have drastically changed the environment. Today, the area is just 25% forest, 15% tea garden, 43% cultivated and non-cultivated land and 17% water bodies, residential, hill etc. Click on the coordinates at the top