Lake Waiau is a high-elevation lake located at 13,020 feet (3970 m) above sea level on Mauna Kea, on the island of Hawai'i. It is the seventh highest lake in the USA, and one of very few lakes at all in the state of Hawai'i. It is relatively small, only about 100 m across, and varies in size as the water level rises and falls. This photo was taken when the water was very low, you can nee the water line on the opposite shore. The name means "swirling water" in Hawaiian, though it is usually rather placid. Legend has it that a mo'o lives in the lake and occasionally you can see it swim across the surface. I myself have seen something move across the lake, but as there are no fish in the lake, I guess it was the mo'o.
According to Hawaiian mythology, Lake Wai'au is bottomless and is the portal for spirits to travel to and from the spirit world. In ancient time, a chief would throw the umbilical cord of their first son, as soon as it fell off the infant, into the lake. It was to reserve the place for the child's afterlife as a chief. Rituals are still performed occasionally in present days.
My elders have told me that when they were growing up their fathers would go up to lake Wai'au and fill a water gourd with water from the lake. When someone in the home became sick they would drink some of the water and get better. They also said the water was always very cold, even on the hottest days, if you drank from the gourd it was always cold.
Lake Waiau is a sacred site. Visitors should not disturb, enter or drink the water of the lake.