Kolkata (internationally known as Calcutta) the capital of the state of West Bengal is popularly known as the "City of Joy". This is truly a megacity on the banks of the river Ganges. 

If you plan to travel by air, come to the Netaji Subhash Chandra Bose airport which hosts both domestic and international terminals.

This City has 2 big railway junctions (Howrah and Sealdah) that serve as gateways for journeys to and from any part of the country.

If you are coming from one of the railway stations, it is better to hire a taxi from the pre-paid taxi booth. The pre-paid taxi fare is marginally higher than normal (approximately Rs. 180-250)  but it is a surer and safer mode of transport.

Climate
The winter months, from November to February are cool, sunny, dry and very pleasant. Light woolen clothing is necessary during winter in Kolkata.

1. Victoria Memorial
2. Birla Planetarium
3. Eden Gardens
4. Science City
5. Nicco Park
6. Indian Museum
7. National Library
8. Kalighat Temple
9. Sunderbans Tiger Reserve -- this is the world's largest and a unique water National Park with spectacular scenery only 3-4 hours from Calcutta. One can easily spend 3-4 days here. Also see this for more information