Once we arrive, we will begin a hike through the dense, lush, tropical rainforest that surrounds the Tenorio National Park. You and your nature guide can go at your own pace and you’ll learn interesting things about the rainforest along the way. When we arrive to Los Tenideros, where two rivers come together, you’ll be amazed at the celestial turquoise blue water color that comes from the waterfall. But for a more scientific explanation, the celestial blue color is created when the inerals in the water: aluminum, silicon and oxygen are suspended in the water and refracts light from the sun so that the flow looks blue.