On the sides of old buildings, you’ll find ghost signs that tell a lot of our history if you just stop and notice them.

You've likely looked at hundreds of these ghost signs without actually seeing them. They literally fade into the background. But if you look closely, each one has a story to tell.

“So many times we're like walking looking at the ground,” said ghost sign expert Tom Dobrowolsky. “Then you like look up, you're like whoah!”

But it can turn into a treasure hunt. Tom Dobrowolsky is the founder of a website called Urban Archives. He is our local expert on ghost signs.

“They're faded. They're kind of ghostly,” said Dobrowolsky. “They're semitransparent representations of themselves.”

From Paul Bunyon Outerwear to an unusual misspelling that's supposed to say Lepper's School of Physician Preparation, these signs speak to us from the past.

“They're so high up on the buildings. You kinda have to look up,” said Dobrowolsky. “They're juxtaposed against the sky. It's kind of like they're speaking down to us from the heavens like departed ghosts.”

Back in their day, they were bright and clear and everywhere.

“It's kind of like opening a city directory from 1900 and seeing oh well what was here? It's like apparently in 1900, we smoked owl cigars,” said Dobrowolsky.

We tend to think that we are the only generation bombarded by advertising, but hovering above the buggies and bowlers and long dresses, you were enticed by everything from filing cabinets and stationery to cameras and steamship tickets.

“Back in the time when these things were dominant mode of advertising, oh great another advertisement on the side of a building,” said Dobrowolsky. “But now they're kind of, oh they're kind of artistic, they're historical, they're charming.”

And mysterious. Part of the fun is cracking the code.

“It's kind of like learning how to read and trying to figure out what it's trying to say and there's so many layers on that sign,” said Dobrowolsky.

The Mohawk Apartments says "for vacant lots in this vicinity,” but when you squint you see "king size Coke" in the green above.

You'd think construction and graffiti would be ghost signs' primary enemies, but not always…

“If they were to build up a building here, it would actually preserve the sign because it would shield it,” said Dobrowolsky.

And knocking down a building can reveal a sign or two. As for graffiti...

“The taggers kinda leave them alone,” said Dobrowolsky. “I don't know if it's some kind of artistic respect or something or it's a way of saying ‘hey that's pretty cool.’”

Tom says the major threat is time.

“It's not like you're going to go and repaint these because that wouldn't be honest,” said Dobrowolsky. “So then what do you do? Do you let them fade away slowly?”

So the next time you take a stroll around town, do stop and smell the roses, but don't forget to read the writing on the wall too.