There is a new optical illusion baffling the world. 

A German app posted a photo of some picnic tables after a party, but the thing that's causing all the confusion is the background. 

To some people, it looks like the property sits on a river, but others are certain that the yard is actually surrounded by a wall. 

The folks who swear it's a river point out what looks like a boat next to the orange box, while Team Wall defend their case by saying you can see shadows from the plants on the "wall." 

It should be noted that the geotag on the photo is Meerbusch, a German town with a river that runs through it.

What do you think?

Photo Credit: Getty