The Calcutta Swimming Club (mainly known by its acronym CSC),in Kolkata, is the oldest swim club in India. The club was built in 1887 and celebrated its Golden Jubilee in 1937. It was renamed the Calcutta Swimming Club in 1941. The club boasts an open air swimming pool that is one of the largest not only in India but also in Asia.

Source: http://en.wikipedia.org/wiki/The_Calcutta_Swimming_Club