The saying goes that a rock fallen from the mountain blocked the Bicaz River course and formed the lake. Actually, the interesting fact about this lake is not the way in which it formed itself not even its colour (which is not red as its names states it but yellowish) but its rather spectacular aspect. Nearly two hundred years ago or so in the place of this lake there was a forest.
Nowadays the lake looks like a sunken forest.Throughout the lake the former tree-trunks can be seen coming out of the water.The lake is situated at an altitude of 983 m in a small mountain depression, a world unique region where the forests of evegren fir-trees and the air pure and invigorating offer good resting conditions.
The lake's name comes either from the Ucigasul (Killer) Mountain or the Rosu (Red) Brook which is also called Verescheu.
One of the popular legends makes the connection between “red” and “killer” recounting that in its fall the mountain buried a flock of sheep with shepherds and dogs and all and for a long time the water remained blood-red.
Another legend relates that once there lived in Lazarea a magnificently beautiful girl whose name was Estera. One day she went to the market and there she met a handsome young man with whom she fell in love there and then. The young man asked her to be his bride. But he had to go into the army and Estera, while she was waiting for him, used to go every evening to the spring to fill her pitcher with fresh water and remained there for hours and hours. One evening, the bad luck brought a bandit to the spring. As he saw her he liked her and kidnapped her taking her among the thousand facets rocks where he lived. Desperate, Estera called the mountains imploring for help. The rocks, impressed by the girl's grieved cries responded with thunders. Instantly a rainstorm started making a clean sweep of everything in its way. Under the broken rocks remained both the girl and the bandit. Afterwards all the mountain's waters gathered in that very place. And thus formed the Red Lake (Lacul Rosu) or … the Killer.