The Lilajan River (also known by its Sanskrit name: Niranjana) is a river that flows through the Chatra and Gaya districts in the Indian states of Jharkhand and Bihar. It is also referred to as the Nilanjan, Niranjana or Falgu River

Nairanjana River ( Pali Neranjara; Nirenzen-ga): The present-day Lilaja River in the state of Bihar, India. This body of water proceeds northward and flows finally into the Ganges River. After leaving the royal palace, Shakyamuni practiced austerities for six years (ten or twelve according to some accounts) on the shore of this river in a forest that was part of the village Uruvilva. Eventually he became aware that practicing austerities would never lead to enlightenment. He bathed in the Nairanjana River, and then, accepting milk curds offered by a girl named Sujata, recovered his strength. He proceeded to the nearby pippala tree and sat beneath it. There he entered meditation and attained enlightenment. Hence the tree was later called the bodhi (enlightenment) tree, and this site, Buddhagaya, or Bodh Gaya.