Kolkata Metro, managed by the Indian Railways, is the oldest underground system India.It parallel to the river Hooghly and spans the length from north to south of the city over a distance of 16.45 km. Buses are the preferred mode of transportation and are managed by both government agencies and private operators. India Kolkata is the only city to have a tram network, operated by Calcutta Tramways Company. The slow tram services are limited to certain areas of the city. Congestion water due to heavy rains during the monsoon season sometimes interrupts public transport. The Vidyasagar SetuHired forms of motorized transport include the counters of yellow taxis, while in auto rickshaws on the road. Almost all taxis are ambassadors in Kolkata. This is unlike most other cities where Tata Indica and Fiat are more common. In some parts of the city, cycle rickshaws and hand-rickshaws were also fired patronised by the public for short distances. Private vehicles are fewer and use compared to other major cities because of the abundance of both the variety and number of public vehicles. However, the city has seen a steady increase in the number of vehicles registered, the data for 2002 showed an increase of 44% over a period of seven years. The road space (along with the population density) in the city is only 6%, compared to 23% in Delhi and 17% in Mumbai, creating major traffic problems. Kolkata Metro Railway and a number of new roads and overflights have decongested traffic to a certain extent.

Kolkata has two major railway stations long distance Howrah and Sealdah Station. A third station in Kolkata was launched in early 2006. The city is the headquarters of two divisions of the Indian Railways - Eastern Railway and South Eastern Railway. The only airport in the city, the Netaji Subhash Chandra Bose International Airport at Dum Dum north of the city, operates both domestic and international flights. Kolkata is also an important riverport in eastern India. The Kolkata Port Trust manages both the banks of Kolkata and Haldia docks. There is a passenger service to Port Blair in the Andaman and Nicobar Islands and cargo services at various ports in India and abroad, managed by the Shipping Corporation of India. In addition, there are ferry services connecting Kolkata with its twin city of Howrah.

Bengalis account for the majority of the population in Kolkata, with Marwaris and Bihari communities forming a large proportion of minorities. Some of Kolkata's notable are the Chinese communities, the Tamils, Marwaris, Gujaratis, Oriya, the Anglo-Indians, Armenians, Tibetans, Maharashtrians and Parsis. Main languages spoken in Kolkata are Bengali, Hindi, Urdu, English, Oriya, and Bhojpuri. According to the 2001 census, 77.68% of the population of Kolkata are Hindu, Muslim 20.27%, 0.88% and 0.75% Christian Jains. Other minorities, such as the Sikhs, Buddhists, Jews and Zoroastrians are the rest of the population of the city. 1.5 million people, who account for about a third of the city's population, recorded live in 2011 and 3500 unregistered (squatter) slums. Kolkata reported 67.6% of all special laws and local (SLL) crimes recorded in 35 Indian megacities. Kolkata police district IPC 10757 cases recorded in 2004, which is the 10th highest in the country. The crime rate in the city was 81.4 per 100000 against the national rate of 168.8 in 2004.Kolkata's Sonagachi area, with more than 10000 sex workers, is one of the largest in Asia red - light districts.