Left: Horsetail Falls, 2011. Photo: Joe Azure Right: The Firefall. Photo: National Park Service
The window is closing on a yearly glimpse of a natural phenomena at Yosemite National Park, during which the angle of the sun and the flow of water off the park's Horsetail Falls commingle in such a way that the waterfall glows, as if aflame. On the ground, photographers come from all over the world to freeze the image on their cameras, as in the photo above, left.
But for nearly 100 years, from 1872 until 1968, a flow of actual fire descended off the the park's Glacier Point, a vista point some 3,000 feet above the valley floor, as in the photo above, right.
The Firefall, as it was called, was set each night during summer. Park officials would collect Red Fir tree bark and set a large bonfire at Glacier Point each day. At 9pm, park workers would take long-handled rakes and push the embers off the cliff, to create the illusion of a waterfall of fire. This was all done to the delight of park visitors, who would convene in Curry Village in the valley to view the spectacle.