It's not unusual for tourists to travel from far and wide to appreciate America's natural wonders.
Every day, the country's 58 national parks fill with hikers, photographers, and outdoorsy folk of all sorts hoping to take in the sights.
But visitors are rushing to Yosemite National Park to capture a very unusual natural wonder: a glowing waterfall of "fire" that doesn't actually exist.
For a few days in February each year, a stream of orange, glowing, molten lava seems to stream over the park's Horsetail Fall. Every night during that time, tourists line up by the hundreds to take in the sight and capture a rare snapshot of the "firefall" in motion.
So what are they actually seeing? It's really just a trick of the light.
As light from the setting sun strikes the 1,570-foot waterfall at just the right angle, it turns the stream bright orange, and seems to illuminate the cliff face around it for up to 10 minutes.
The exact look of the firefall depends on weather conditions and the amount of water flowing over Horsetail Fall (during a drought from 2014 to 2016 the firefall disappeared). But visitors who get a good look at the phenomenon agree it's worth standing in the cold for hours to see.
If you live close to California and want to see the firefall in person, there's a $35 entrance fee for Yosemite but no other costs or reservations to make. The thing is, space in the viewing area is first come first serve, so plan to get there in the early afternoon.
It's a mile's walk from the Yosemite Falls Parking Area to the spectating area, so be sure to bring comfy footwear and warm clothes.
Horsetail Fall glistens in the setting sun at @YosemiteNPS creating a lava like effect known as #firefall for the viewers below. This was, without a doubt, one of the coolest sights I've ever been lucky enough to witness. pic.twitter.com/YYPZB5rzHC— Brady Kenniston (@TheFavoritist) February 19, 2019
And, of course, there's no guarantee Yosemite will put on a good show for you, even after all that time and effort.
The nightly event is expected to stay visible until February 24.