In Kolkata, a city of culture, history and festivals, the third Sunday in December is a date which is eagerly anticipated as it brings the Procam International-promoted running festival, The Tata Steel Kolkata 25K. In addition to this, there are plenty of marathon events in Kolkata. Some of the popular ones are the Kolkata Marathon, the Great Kolkata Run, and the Kolkata Half Marathon.

The Kolkata Marathon is an annual marathon race held in Kolkata, India. The race is organized by the Kolkata Marathon Association and is sanctioned by the Athletics Federation of India. The race is held in late November or early December. The race has been held annually since 2009. The race course starts and finishes at the Victoria Memorial. The race has three categories: a full marathon, a half marathon, and a 10K race. The full marathon course is 42.195 kilometers in length. The half marathon course is 21.0975 kilometers in length. The 10K race course is 10 kilometers in length. The Kolkata Marathon is one of the largest running events in India. The event typically attracts around 20,000 runners each year.