Delhi Union territory and Megacity National Capital Territory of Delhi From top clockwise: Lotus temple, Humayun 's Tomb, Connaught Place, Akshardham temple and India Gate Location of Delhi in India Coordinates: 28 ° 36 ′ 36 '' N 77 ° 13 ′ 48 '' E ﻿ / ﻿ 28.61000 ° N 77.23000 ° E ﻿ / 28.61000; 77.23000 Coordinates: 28 ° 36 ′ 36 '' N 77 ° 13 ′ 48 '' E ﻿ / ﻿ 28.61000 ° N 77.23000 ° E ﻿ / 28.61000; 77.23000 Country India Settled 6th century B.C. Incorporated 1857 Capital formation 1911 Formation of Union Territory 1956 Formation of NCT 1 February 1992 Capital New Delhi Districts 11 Government Body Government of Delhi Lt. Governor Anil Baijal, IAS Chief Minister Arvind Kejriwal (AAP) Deputy Chief Minister Manish Sisodia Chief Secretary Anshu Prakash, IAS Commissioner of Police Amulya Patnaik, IPS Area Union territory 1,484.0 km (573.0 sq mi) Water 18 km (6.9 sq mi) Area rank 31st Elevation 200 -- 250 m (650 -- 820 ft) Population (2011) Union territory 16,787,941 Density 11,312 / km (29,298 / sq mi) Urban 16,349,831 (2nd) Megacity 11,034,555 (2nd) Metro (2016) 26,454,000 (1st) Demonym (s) Delhiite Languages Official Hindi English Additional official Punjabi Urdu GDP Nominal (NCT) ₹ 6.86 lakh crore (US $100 billion) (2017 - 18) Nominal per capita ₹ 329,093 (US $4,800) (2017 - 18) Metro GDP / PPP $167 -- 370 billion Time zone IST (UTC + 5.30) Pincode (s) 1100XX Area code (s) + 91 11 ISO 3166 code IN - DL Website delhi.gov.in
when was delhi declared as capital of india
1911