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

On the west coast of Ireland, on the banks of an estuary dividing county Limerick from County Clare,

lies a small town called Shannon.

But Shannon is not a quaint fishing village or a farming community.

Its industry is its airport.

And Shannon Airport is big.

It handles up to 1.7 million passengers and 20,000 flights a year,

most of them from other countries.

And a few months ago, I went to visit.

That's reporter Kevin Caners. When you arrive at the airport

you're greeted by a modern looking building that's sleek and black and when you

enter through the sliding doors and step into the checking area you find yourself in a bright grand atrium with

wooden furnishings and tall ceilings. It's a style that you might call international

terminal chic. Everything attests to a certain kind of reassuring cosmopolitan competence.

But my reason for entering the terminal wasn't to catch a flight to Myorca or Warsaw,

or to pick up a friend.

It was to visit its duty-free shop.

Okay, and this is it? The duty-free shop?

Yeah, yeah, we're in our duty-free shop here in the airport.

The world's first airport duty-free shop. The fact is the first duty-free shop.

The fact is the first duty-free shop.

Now we take pride in it. It's unique. It's ours and it always will be ours.

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