The Blue Lake Rhinocerous was buried under ancient lava flows. It was discovered in 1935, when four people from Seattle were searching for petrified wood in the Blue Lake basin. After spotting a cave in a rock wall, they crawled inside and discovered bones lying around. Scientists later determined that the bones belonged to some kind of rhinocerous. After investigation, the Blue Lake Rhino is considered to be a rhino that spouted two horns growing side by side on its snout.