Koshi Province is an autonomous province of Nepal adopted by the Constitution of Nepal on 20 September 2015. It covers an area of 25,905 km², about 17.5% of the country's total area. With the industrial city of Biratnagar as its capital, the province includes the towns of Birtamod, Sundar Haraincha, Damak, Dharan, Itahari, Triyuga Municipality and …Koshi Province is an autonomous province of Nepal adopted by the Constitution of Nepal on 20 September 2015. It covers an area of 25,905 km², about 17.5% of the country's total area. With the industrial city of Biratnagar as its capital, the province includes the towns of Birtamod, Sundar Haraincha, Damak, Dharan, Itahari, Triyuga Municipality and Mechinagar, and Mount Everest, Kangchenjunga and Ama Dablam. Koshi River, the largest river of the nation, forms the province's western boundary. Under the First-past-the-post voting system issued by the Constituency Delimitation Commission, Nepal, the province hosts 28 parliamentary seats and 56 provincial assembly seats. The province is bordered by the Tibet Autonomous Region of China to the north, the Indian states of Sikkim and West Bengal to the east, Bihar to the south, and Bagmati Province and Madhesh Province to the west. According to the 2021 Nepal census, there are around five million people in the province, with a population density of 190 per square kilometre. In the 2011 Nepal census, the province had approximately 4.5 million people.