Karnataka's smallest district, Kodagu, is a major contributor to Indian field hockey, producing numerous players who have represented India at the international level. The annual Kodava Hockey Festival is the largest hockey tournament in the world. Bangalore has hosted a WTA tennis event and, in 1997, it hosted the fourth National Games of India. The Sports Authority of India, the premier sports institute in the country, and the Nike Tennis Academy are also situated in Bangalore. Karnataka has been referred to as the cradle of Indian swimming because of its high standards in comparison to other states.