Known as the Tea City of India, Dibrugarh is located in the easternmost part of Assam at 354 feet above sea level. It is an important industrial area of the Dibrugarh district. The region is flat with a gradual slope from the eastern Arunachal hills, with rich alluvial soil of the river Brahmaputra. The river and its tributaries (Dihing) divide the Dibrugarh district from east to west. Assamese is the native and most widely spoken language. The city has a population of 1,30,000 and according to the data of the 2011 census, the total population of the district is about 1.3 million. 30 percent of this population is of working age, out of which 40 percent are involved in agricultural activities. More than 57 percent people are employed in the vast industrial activities related to Oil and Natural Gas, Tea Processing and Power Generation. With the mighty Brahmaputra and Dihing Rivers flowing through the region, Dibrugarh served as one of the most important military, administrative, commercial and industrial bases for the British.