++CLIENTS PLEASE NOTE: THIS VIDEO HAS BEEN LOOPED++ This hiker encountered a bizarre phenomenon close the French border in northern Spain where they found a stream that was running uphill.

Filmed in Guils de Cerdanya on the GR11 hiking trail, the footage shows how the stream's water going uphill appearing to defeat the laws of gravity.

The strange occurrence is caused by "Gravity Hills," which are described as "a place where the layout of the surrounding land produces an optical illusion, making a slight downhill slope appear to be an uphill slope."

The filmer explained the moment: "I was hiking at the GR11-trail in Spain, summer 2018 when I encountered this stream that looked like it ran uphill.

"I was standing there for a long time trying to figure out what was going on, but I couldn't figure it out.

"Later learned about gravity hills."

I was hiking at the GR11-trail in Spain sommer 2018, when I encountered this stream that looked like it ran uphill. I was standing there for a long time trying to figure out what was going on, but I couldn't figure it out. Later learned about gravity hills.