The Central Himalayas encompasses the areas with the highest topographic relief. The Central Himalayas is again separated into four zones:The High Himalayan Crystalline Sequence (HHCS)The Tethys Himalaya (TH)The Nyimaling-Tso Morari Metamorphic Dome (NTMD)The Lamayuru and Markha Units (LMU)
North-Eastern Zonal Council has eight states viz, Sikkim, Arunachal Pradesh, Meghalaya, Nagaland, Manipur, Mizoram, Tripura, Assam. Taking states and UTs together, the Northern zonal council has the maximum number of states and UT.
The high concentration of jute mills in the Hooghly basin are because of the presence of lot of water which is easily available from the Hugli River. Iron and coal also available from Raniganj mines. The suitable type of climate (24°C to 35°C temperature, rainfall of 120 to 150 cm, 80 to 90 % relative humidity ) is found in West Bengal.