Ludhiana is a city and a municipal corporation in Ludhiana district in the Indian state of Punjab. It is the largest city in Punjab, with an estimated population of 1.4 million. The population increases substantially during the crop harvesting season due to immigration of laborers from states like Uttar Pradesh, Bihar and Delhi. It has an area of about 310 km˛. The city stands on the Sutlej River's old bank, 13 km south of its present course.
Ludhiana is centrally located on the National Highway 1 from Delhi to Amritsar, and is connected to the Indian capital city of New Delhi by road and frequent train service.It is a major industrial center of northern India.