Urban structure :

Kolkata city, under the jurisdiction of the Kolkata Municipal Corporation (KMC), has an area of 185 km2 (71 sq mi). The Kolkata urban agglomeration, however, has continuously expanded and as of 2006, the urban agglomeration (Kolkata Metropolitan Area) is spread over 1,750 km2 (676 sq mi), and comprises 157 postal areas. The urban agglomeration is formally administered by several local governments including 38 local municipalities. The urban agglomeration comprises 72 cities and 527 towns and villages. The suburban areas of Kolkata metropolitan district incorporates parts of the districts North 24 Parganas, South 24 Parganas, Howrah, Hooghly and Nadia.

The east-to-west dimension of the proper city is narrow, stretching from the Hooghly River in the west to roughly the Eastern Metropolitan Bypass in the east, a span of barely 5 km (3.1 mi)–6 km (3.7 mi). The north-south expansion is roughly divided into North, Central and South Kolkata. North Kolkata locality is the oldest part of the city, with 19th century architecture and narrow alleyways. South Kolkata grew mostly after independence and consists of well-to-do & posh localities like Ballygunge,Bhowanipore,Alipore,New Alipore & Jodhpur Park localities. The Salt Lake City (Bidhannagar) area to the northeast of the city is a planned section of Kolkata. Rajarhat, also called New Town, is a planned township being developed on the north-eastern fringes of the city. Also,the areas on E M Bypass,where the new developments are taking place, are the newly upcoming upscale-localities of the city.

Central Kolkata houses the central business district around the B. B. D. Bagh area. The government secretariat, General Post Office, High Court, Lalbazar Police HQs and several other government and private offices are located here. The Maidan is a large open field in the heart of the city where several sporting events and public meetings are held. Several companies have set up their offices around the area south of Park Street which has become a secondary central business district.