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

I fell in love with architecture in Chicago, a city known for its pioneering stunning skyscrapers.

Every good thing you hear about Chicago architecture is true.

And whenever anyone I know takes a trip to Chicago,

I tell them, the one thing that you have to do is go on the Chicago Architecture Foundation Center boat tour.

From the river, you can take in all these amazing buildings, while a whip-smart passionate docent tells you story after story

of grand ambitions and visionary architects.

But it's important to note that only a small percentage of structures are designed by architects.

And while an iconic building along the skyline might be the best way to identify a city at a distance,

up close, it's the subtle cues and vernacular

design that make the city what it is.

If someone were to blindfold me, spin me around and drop me in one of Chicago's

1900 miles worth of alleyways, I would know what city I was in instantly,

not because I could see the Sears Tower, but because from almost any alley, you can see these hefty, robust wooden fire escapes climbing up the backs of two, three, and four-story brick apartment buildings.

To call it a firescape is almost a misnomer.

They usually have a substantial landing on each floor,

so they serve as a de facto porch. a down in the alley below. These wooden steps and porches started popping up in the

early 1900s, bolted onto buildings as a means of emergency escape because of

Chicago's very justified fear of fire.

They were utilitarian affairs that became so much more.

It's safe to say that the vast majority of these were not designed by architects. The one on the back of my

apartment building in Logan Square was so structurally unsound I don't think it

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