Every February, when weather conditions allow, Horsetail Fall on the eastern side of El Capitan appears to turn into a waterfall of fire or molten lava. It comes to life when the setting sun causes light to hit the waterfall at just the right angle. You can only see "Firefall" for a short time in February, and it draws hundreds of visitors to Yosemite National Park in California each night. How it looks varies from year to year, and relies on how much water is flowing in Horsetail Fall.
The Merced River is most well known for its swift and steep course through the southern part of Yosemite National Park, where it is the primary watercourse flowing through Yosemite Valley. The river's character changes dramatically once it reaches the plains of the agricultural San Joaquin Valley, where it becomes a slow-moving meandering stream.
