Old Delhi (Hindi: पुरानी दिल्ली; Urdu: پُرانی دلّی; Purānī Dillī), walled city of Delhi, India, was founded as Shahjahanabad (Persian: شاه جهان آباد) by Mughal Emperor Shahjahan in 1639. It remained the capital of the Mughals until the end of the Mughal dynasty. It was once filled with mansions of nobles and members of the royal court, along with elegant mosques and gardens. Today, despite having become extremely crowded and dilapidated , it still serves as the symbolic heart of Islamic metropolitan Delhi.
Delhi (/ˈdɛli/, also known as the National Capital Territory of Delhi is a metropolitan region in India that includes the national capital city, New Delhi. It is India's second-most-populous city after Mumbai, and the largest city in terms of area. With a population of 22 million in 2011, the city is the fourth-largest city 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 NCR includes the neighbouring cities of Baghpat, Gurgaon, Sonepat, Faridabad, Ghaziabad, Noida, Greater Noida and other nearby towns, and has nearly 22.2 million residents.