This is 99% invisible. I'm Roman Mars.

In 1928, a strange phenomenon was sweeping the state of Idaho, a vanishing act of sorts.

A poise resident would wake up on a typical Monday morning,

drag themselves out of bed, get dressed for the day, and they would hop in their car to drive to work,

not noticing that something was missing. And suddenly, cops in the rear view.

Then the next thing that the driver of the car knew, they were getting picked up because they weren't

displaying an license plate. Idaho's historian Rick Just says license plates,

well they were disappearing. The Secretary of State was fielding complaints about all the lost

tags, and soon enough, the culprit became clear. Tourists would come to Idaho and steal the plates.

Idaho's license plates were being snatched up like plush hotel bathrooms.

Yeah, yeah. People would come up, they would pull up to either a tourist park or a motel or something,

and they would spot those plates and think, you know, I'd like to have a souvenir,

and so they would just take it off of the car and take it home.

And there was a reason why people couldn't resist swiping Idaho plates in particular.

That year, the state had revolutionized license plate design.

That's reporter Daniel Akerman.

Before this, plates were basic with info like the state name and the registration numbers.

All of this on a pretty simple solid colored background. But in 1928, the Secretary of State in

Idaho had an epiphany. He was like, we have this half square foot of open real estate just rolling

around on everyone's cars. Let's do something with it. The 1928 plate is often said to be the very

first advertising license plate in the country. They're very first one that tried to advertise a product.

In the product that Idaho chose, we'll surprise absolutely no one.

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