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

In the early 1970s, when March of unputin was 21 years old, she lived in an apartment with her young kid in the middle of

Amsterdam. It was right on a busy road and there was always a lot of traffic.

I remember there was a nearby school and you could see before 9 o'clock before the school start children on their bikes

crossing that road to go to school at the other side of that busy road.

Marcher worried about the kids on their bikes.

Once in a while there were accidents.

And one day she heard a collision out on the street.

Some people were screaming and other cars had to stop and you could hear their alarms and things. So then you run to the

window and you see what's happening. A girl about eight years old had been

trying to cross the street and got hit by a car. She was luckily not so seriously hidden that she had to be transferred to a hospital,

but she was hit and the bike was broken.

And there was a lady, at that time an old lady someone as I am now

an old lady with an umbrella like this Mary Poppins sort of type

Marja watched as the Mary Poppins sort of type. Marja watched as the Mary Poppins lady approached the driver of the car.

She took the point of her umbrella and she poked it right into his stomach.

And she was screaming at him and I was standing at the window and you could see what was happening.

That kind of things, you know, you don't forget.

In the early 1970s, this kind of collision was all too common.

Producer Delaney Hall.

There were more cars on the Dutch roads than ever before,

and the roads were getting more dangerous.

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