Ludhiana (Punjabi: ਲੁਧਿਆਣਾ) is a city and a municipal corporation in Ludhiana district in the Indian state of Punjab, and is the largest city, north of New Delhi. It is the largest city in the state, with an estimated population of 1,618,879 as per Census 2011.The population increases substantially during the harvesting season due to the migration of labourers from the eastern states of Uttar Pradesh, Bihar, Odisha and Delhi. It has an area of about 310 km². The city stands on the Sutlej River's old bank, 13 km south of its present course.