The name of the lake literally means "lake of the demon" in Sanskrit. It is also known as Ravan Tal, as it is considered to be the place of severe penance by Ravan, the demon-like egoistic King of Lanka in Hindu theology.
Why is Lake Rakshastal the “lake of the demon”?
In Buddhism, Lake Manasarovar, which is round like the sun, and Rakshastal, shaped as a crescent, are respectively regarded as "brightness" and "darkness". Its salty water, in stark contrast to the fresh water of Lake Manasarovar, results in there being no aquatic plants or fish, and is considered poisonous by locals. It is a belief that the short river named Ganga Chhu, which connects Lake Manasarovar with Rakshastal, is created by rishis to add pure water from Manasarovar.
There are four islands in Rakshastal, named Topserma (Dose), Dola (the two biggest), Lachato (Nadzhado), and Dosharba. The islands are used by local people as winter pastures for their yaks.
According to Hindu scriptures, Rakshastal was created by Ravana for the express purpose of garnering superpowers through acts of devotion and meditation to the god, Shiva, who resided on Mount Kailash. It was upon the banks of a special island in this lake that he would make a daily offering with one of his ten heads as a sacrifice to please Shiva. Finally, on the tenth day, Shiva was moved enough by his devotion to grant Ravana his wish to obtain superpowers.
The scenery of the lake is gorgeous. Walking on the road beside the lake, you can appreciate the enchanting scenery -- the peaceful water with changing colors, white, blue and dark blue all integrated. The vast lake with few moving animals and people may give you an illusion that you may have arrived at the edge of the universe.
How to get to Lhanag-tso:
Heading for Burang County from Mt. Kailash and Manasarovar, you can pass the demon lake. The road is less than 1km from the lakeside.