Province No. 1  Province No. 1 (proposed names: Koshi/Purbanchal) is the easternmost of the seven provinces established by the new constitution of Nepal which was adopted on 20 September 2015. With the industrial city of Biratnagar as its headquarter, the province covers other major eastern towns including Damak, Dharan, Itahari, Inarua and Birtamod and includes several mountains including the Everest, Kanchenjunga, and Ama Dablam. Koshi - the largest river of the nation, circumvents the province's western boundary. Adhering to the first-past-the-post voting system issued by the Constituency Delimitation Commission, the province hosts 28 parliamentary seats and 56 provincial 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, and Bihar to the south, and Bagmati Pradesh and Province No. 2 to the west. According to the 2011 census, there are around 4.5 million people in the province, with a population density of 175.6 per square kilometer. At the end of Rana regime, Nepal was divided into 32 districts. Eastern Nepal (Province No. 1) contained following districts: In 1956, eastern districts of Nepal grouped in a region named "Arun Kshetra". Arun Kshetra was composed by grouping the then 5 districts. Those 5 districts are now divided into many districts. Arun Kshetra had total area of and total population was 11 Lakhs. The five districts were:  In 1962, administrative system restructured and the "Kshetras" system cancelled and the country restructured into 75 development districts and those districts were grouped into zones. In 1972 area of the Province No. 1 named Eastern Development Region. It had 3 zones and 16 districts. As per the cabinet meeting held on 17 January 2018, the city of Biratnagar was declared the interim capital of Province No. 1. It was later declared as the permanent capital on 6 May 2019 when two-third of the provincial assembly's MLAs voted in favor of Biratnagar. Province No. 1 covers an area of 25,905 km2. The Province has three-fold geographical division: Himalayan in the north, Hilly in the middle and Terai in the southern part of Nepal, varying between an altitude of 70 m and 8,848 m.