Thane district (Pronunciation: [ʈʰaːɳe], previously named Taana or Thana) is a district in the Konkan Division of Maharashtra, India. At the 2011 Census it was the most populated district in the country, with 11,060,148 inhabitants; however, in August 2014 the district was split into two with the creation of a new Palghar district, leaving the reduced Thane district with a 2011 Census population of 8,070,032. The headquarters of the district is the city of Thane. Other major cities in the district are Navi Mumbai, Kalyan-Dombivli, Mira-Bhayander, Bhiwandi, Ulhasnagar, Ambarnath, Badlapur, Murbad and Shahapur. The district is situated between 18°42' and 20°20' north latitudes and 72°45' and 73°48' east longitudes. The revised area of the district is 4,214 km2. The district is bounded by Nashik district to the north east, Pune and Ahmednagar districts to the east, and by Palghar district to the north. The Arabian Sea forms the western boundary, while it is bounded by Mumbai Suburban district to the south west, and Raigad District to the south. From Wikipedia
