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

Oh God! Thank you, thank you, thank you!

My whole damn life has been worth it.

Yes, for this whole thing. So I was once walking the city with my friend Kathleen who was an environmental scientist and she was pointing out the spray painted markings of letters and arrows that you see everywhere on the street.

The markings indicate where utility lines are running underground so they're not damaged by construction.

And it turns out they're color-coded by the American Public Works Association.

Red spray paint means electrical power lines and yellow is natural gas.

And I'm looking this up now on Wikipedia because I don't remember all the details.

Green means sewage and drainage lines.

So public works people and construction crews have their own low-fi augmented reality

scribbled right on the street, like a giant map in plain sight.

It's a different way to see the city.

But it's not just utility workers.

The city also reads differently depending on your knowledge,

your experience, or if you happen to be standing on a rolling plank of wood.

I've been lucky enough to go to these amazing places like Taiwan or LA, but I only ever

get to see like the weird places that skaters go to, like industrial parks or some handrail

in the middle of a school somewhere.

That's our guide today, skateboard photographer and radio reporter Andrew Norton.

My friend Ariel and I are skating in downtown Toronto, kind of carving through the big, empty corporate plazas.

It's hard with a backpack.

Yeah, I'll give you one of these though.

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