Arunachal Pradesh, 'the land of the dawn lit mountains', is one of the most pristine areas in India . The history of Arunachal Pradesh is a virtual treasure trove of myths and fascinating traditions, but the recorded history of this state is available only from the 16th century onwards, when the Ahom kings began to rule Assam . Since 1947, it was a part of the North East Frontier Agency and was later made a Union Territory . Arunachal Pradesh was made a full fledged state on 20th February, 1987 . The greatest attraction of the state is its dazzling array of flora and fauna, in a habitat that combines glacial terrain, alpine meadows, and sub-tropical rain forests. Places of tourist interest in the state include Bomdila, Tawang and the nearby Buddhist monastery, which happens to be the largest in India . Itanagar is famous for its excavated ruins of the historical Ita Fort, and the attractive Gyaker Sinyi or the Ganga Lake . Malinithan and Bhismaknagar are the two important archaeological sites in the state, and Parashuram Kund is a prominent pilgrimage site. Namdapha Wildlife sanctuary in the Changlang district is home to the rare Hoolock gibbon.