DOWNTOWN — Mike McMains, a Chicagoan known for his unique walking tours of the city, is going underground — and you can come along.

McMains’ Underground Chicago (Plus Rats!) Tour will showcase the city’s hidden underside and discuss how urban wildlife — namely rats — are a part of Chicago’s history. It’s set to kickoff July 22 and tickets are $30.

The 90-minute tour starts at the Ulta Beauty on the Magnificent Mile at 430 N. Michigan Ave. and ends at the Monroe Red Line stop, with several underground stops in between. McMains will discuss how Chicago’s history and architecture are closely intertwined with the rats who also call it home.

McMains, who operates Tours With Mike, often highlights Chicago’s architecture, design and history in tongue-in-cheek ways.

“For a long time, I’ve been fascinated by Chicago’s layers, that you have so much complexity going on above and below what the surface,” McMains said.

The idea for the tour originally came from a man who’d attended one of McMains’ Ugly Building tours, which highlights some of Chicago’s unsightly buildings.

He reached out to McMains to see if there was a tour that discusses the city’s rat history — inspired by his 10-year-old cousin’s fascination with the creatures. McMains himself already had an interest in Chicago’s underground streets, Pedway system and subway stations, and was looking for a way to make them more interesting for a tour.

“I was super excited and … the thing that I really loved about it is that you have a 10-year-old with a very unconventional interest,” McMains said. “And I just love that the family was coming together to rally behind this kid and say, ‘Hey, we’re not going to try to steer you towards something else so that you gonna blend in with society; we want to nurture and support your quirks and your interests.’ I love that they were like, ‘Hey, can you do this?’ I’m just like, ‘Absolutely, I want to do this.’”

For the tour, McMains heavily researched rat anatomy, behavior, and living patterns, including how the Norway brown rat made its way to Chicago from Asia centuries ago. McMains said he believes that rats are a great entryway to discussing Chicago’s underground history, especially since the species reflects some of the city’s best attributes. 

“I really think that rats are so interconnected with the story of Chicago in that they’re adaptable, they’re resilient, they’re scrappy, and their fates are thoroughly interconnected with each other,” McMains said.

“If I didn’t get that random email earlier this year, I don’t think I would be doing this tour. I needed that spark in order to focus on the amazing underground infrastructure Chicago has. You need a story that binds it together, and those are rats.”

Stops on the tour include the Billy Goat Tavern at Lower Michigan Avenue, the Riverwalk and ports of Chicago, the history of the Downtown’s produce markets, the Illinois Central Railroad including Metra and CTA stations and more. People can also expect to see the parts of the Chicago Pedway and Wacker Drive where Christopher Nolan’s “The Dark Knight” was filmed.