What if someone told you there is a lake in Oregon that disappears every year?

Chances are no body would believe that but luckily there is a video showcasing this extraordinary phenomenon.

The Bend Bulletin recently posted this clip on Youtube, showing the Lost Lake draining into a mysterious lava tube in the Central Oregon Cascades, reports Yahoo News.

According to Yahoo News, Jude McHugh, spokesperson for the Willamette National Forest, told the Bulletin that this is something that’s been happening for as long as people can remember.

“It fills up in the winter, when input exceeds the rate of draining, and then it goes dry and it’s a meadow,” McHugh said.

This phenomenon may be rare, but not completely unheard of. Yahoo News reports, a lava tube is formed when lava hardens near the surface, but continues to flow downward, creating a tunnel like structure. Nearby Fish Lake also drains on a seasonal cycle. 

So where does the water go? Honestly, officials aren’t completely sure. They predict that the water seeps into the porous subsurface below, recharging the massive aquifer that feeds springs on both sides of the Cascades.

If you think plugging the lava tube is an option, think again. McHugh said that many have tried and failed to keep the lake from disappearing, which he explains is a good thing for the local infrastructure.

“If anyone was ever successful at plugging it, which we’re not sure they could do, it would just result in the lake flooding, and the road,” said McHugh.