This optical illusion has confused people for days

Penny Burfitt
Lifestyle & Entertainment Producer

There’s nothing like an optical illusion to make your eyes strain and your head hurt, but usually most can figure out what’s going on in a matter of seconds, or minutes at a stretch.

The latest illusion that has the internet scratching its head however, has tied people in knots for days as they try, and fail, to work out what the hell is going on.

The video illusion runs for just 20 seconds, but for those struggling to grasp exactly what it is they are watching, no amount of time will help.

A viral sensation

The video shows cars turning off a street and simply disappearing from view, how exactly is the question on everyone’s lips.

Posted by Twitter user Agus early last month, the video has recently exploded in popularity as it perplexes increasing numbers of people from all over the world.

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The original tweet showing the baffling footage has blown up online, with tens of thousands of likes and comments from people completely floored by the trick of perspective.

Comments show that for many, no matter how long they spent trying to figure it out, the answer was elusive.

What is going on?

What looks like a river seems to be what the cars and motorbikes are disappearing into, though debate has been raging for days regarding what is in the foreground of the shot.

Many believe they are looking at a bridge stretching across a muddy river, which the vehicles are turning off and suddenly disappearing.

What’s really going on is that the roof of a building with a railing around its edge (giving it a sunken look) is in the foreground of the shot, blocking the street that the vehicles are turning into from view.

If that does’t clear it up, the Twitter thread is peppered with helpful diagrams and how-tos to guide you to the truth of the shot.

If you still can't get it, then it’s unclear what can be done.

It’s not the first optical illusion to make people do a double – and sometimes triple – take.

Last month a colour illusion had some seeing this picture in black and white, and some in bright colour.