Delhi, officially the National Capital Territory (NCT) that includes the Indian capital New Delhi, is the second most populous metropolis in India after Mumbai, with a population of 16.3 million in 2011. The city is also the eighth most populous metropolis in the world.The NCT and its urban region have been given the special status of National Capital Region (NCR) under the Constitution of India\\\\\\\'s 69th amendment act of 1991. The greater NCR urban, which includes the neighbouring cities Baghpat, Gurgaon, Sonepat, Faridabad, Ghaziabad, Noida, Greater Noida and other nearby towns, has nearly 22.2 million residents.
Delhi is known to have been continuously inhabited since the 6th century BC.Through most of its history, Delhi has served as a capital of kingdoms and empires. It has been invaded, ransacked and rebuilt several times, particularly during the Medieval era, and therefore the modern city of Delhi is a cluster of many cities scattered across the metropolitan region. Delhi is also believed to have been the site of Indraprastha, the legendary capital of the Pandavas during the times of the Mahabharata.Delhi re-emerged as a major political, cultural and commercial city along the trade routes between northwest India and the Gangetic plain after the rise of the Delhi sultanates.It houses many ancient and medieval monuments, archaeological sites and remains.