Delhi is a metropolitan region in India. With a population of 22 million in 2011, it is the world's second most populous city and the largest city in India in terms of area. The NCT and its urban region have been given the special status of National Capital Region under the Constitution of India's 69th amendment act of 1991. The NCR includes the neighbouring cities of Alwar, Baghpat, Gurgaon, Sonepat, Faridabad, Ghaziabad, Noida, Greater Noida and other nearby towns, and has nearly 22.2 million residents.A union territory, the political administration of the NCT of Delhi today more closely resembles that of a state of India, with its own legislature, high court and an executive council of ministers headed by a Chief Minister. New Delhi is jointly administered by the federal government of India and the local government of Delhi, and is the capital of the NCT of Delhi.Delhi has been continuously inhabited since the 6th century BC. Through most of its history, Delhi has served as a capital of various kingdoms and empires. It has been captured, ransacked and rebuilt several times, particularly during the medieval period, and the modern Delhi is a cluster of a number of cities spread across the metropolitan region. This is why Delhi is sometimes called the City of cities.