Kolkata, formerly Calcutta, is the capital of the Indian state of West Bengal. Kolkata has a great history and is one of the major metropolitan city of India. It is located in eastern India on the east bank of the River Hooghly. The city has a population of almost 4.5 million, with an extended metropolitan population of over fourteen million, making it the third-largest urban agglomeration and the fourth-largest city in India.Kolkata served as the capital of India during the British Raj until 1911.

Once the centre of modern education, science, culture and politics in India, Kolkata witnessed economic stagnation in the years following India's independence in 1947. However, since the year 2000, economic rejuvenation has led to a spurt in the city's growth. Like the other metropolitan cities of India, Kolkata continues to struggle with urbanisation problems like poverty, pollution and traffic congestion.

Kolkata is noted for its revolutionary history, ranging from the Indian struggle for independence to the leftist and trade union movements.Kolkata is located in eastern India at 22°33'N, 88°20'E in the Ganges Delta at an elevation ranging between 1.5 m (5 ft) to 9 m (30 ft). It is spread linearly along the banks of the River Hooghly in a north-south direction. Much of the city was originally a vast wetland, reclaimed over the decades to accommodate the city's burgeoning population.

The remaining wetland, known as East Calcutta Wetlands has been designated a "wetland of international importance" under the Ramsar Convention.Like the most of the Indo-Gangetic plains, the predominant soil type is alluvial. Quaternary sediments consisting of clay, silt, various grades of sand and gravel underlie the city. These sediments are sandwiched between two clay beds, the lower one at depths between 250 m (820 ft) and 650 m (2,133 ft) and the upper one ranging between 10 m (33 ft) and 40 m (131 ft) in thickness.

According to the Bureau of Indian Standards, the town falls under seismic zone-III, in a scale of I to V (in order of increasing proneness to earthquakes) while the wind and cyclone zoning is "very high damage risk", according to UNDP report.