Mumbai Marathon started in year 2004. It takes place every January of the year. In 2007, it will take place on the 21st, January. This event is a part of the "greatest race on earth" circuit. The crowds are always enthusiastic. Running in January, which is one of the mild months in Mumbai can be a brutal test of stamina in the face of heat and humidity.
More on this event. It is sponsored by the Standard Chartered Bank.