Kaziranga National Park is a national park in the Golaghat and Nagaon districts of the state of Assam, India. A World Heritage Site, the park hosts two-thirds of the world's Great One-horned Rhinoceroses. Kaziranga boasts the highest density of tigers among protected areas in the world and was declared a Tiger Reserve in 2006. The park is home to large breeding populations of elephants, wild water buffalo, and swamp deer. Kaziranga is recognized as an Important Bird Area by Birdlife International for conservation of avifaunal species. The history of Kaziranga as a protected area can be traced back to 1904, when Mary Victoria Leiter Curzon, the wife of the Viceroy of India, Lord Curzon, visited the area. After failing to see a single rhinoceros, for which the area was renowned, she persuaded her husband to take urgent measures to protect the dwindling species which he did by initiating planning for a their protection. On 1 June 1905, the Kaziranga Proposed Reserve Forest was created with an area of 232 Sq. km. The cancellation depicts one horned Rhino.