It is New Delhi. Also referred as delhi. The name Delhi also refers to the National Capital Territory of Delhi (NCT), which is a special union territory jointly administered by the Central government, the NCT elected government and three municipal corporations. The metropolis of Delhi and the National Capital Territory of Delhi are coextensive and for most practical purposes they are considered to be the same entity. New Delhi, an urban area within the metropolis of Delhi, is the seat of the Government of India.
With a population of 15.3 million people (2005 figure), Delhi is the seventh most populous metropolis in the world . Delhi's metropolitan area, informally known as the National Capital Region (NCR), comprises the NCT, the neighbouring satellite towns of Faridabad and Gurgaon in Haryana, and NOIDA and Ghaziabad in Uttar Pradesh. Altogether, the NCR is the world's sixth most populous agglomeration with a population of 19.7 million.
Delhi was the capital of several empires in ancient India and has over 60,000 recognized monuments erected over several millennia. Delhi derives its historic importance from its position in northern India between the Aravalli Hills to the southwest and the Yamuna River to the east. This enabled it to dominate the old trade routes from northwest India to the Gangetic Plains. As a result, it has long been an important cultural, political, and intellectual centre. Due to a high migration rate, Delhi registers as one of the fastest growing cities in Asia.