River rafting on the Kosi River flowing alongside the Corbett National Park is the adventure activity one can participate in while on the Corbett tour. But rafting in the Kosi isn’t as exciting as rafting in other famous rivers as in the Ganga River, but in Corbett you’ll enjoy this adventure activity. River rafting in the Kosi River can only be undertaken during the Monsoon season when the river’s water level is high.