While this firefall in Yosemite National Park isn’t lava cascading down the side of a volcano, it is an optical illusion that occurs each year when “the elements are perfect for the last of the day’s sun rays to strike Horsetail Falls, creating a magical luminance.” Video after the break. Click here for more pictures.

At about 5.30pm local time, when the sun begins to set, the shadows lengthen, and the rays hit the top of the rock face, a miraculous transformation takes place. It is then that the beautiful natural illumination is created.

[via DailyMail]