From numerous suspension bridges, a national shrine and the International Museum of Surgical Science, Chicago boasts many pockets of history, and during Open House Chicago, you can tour these hidden gems in person for free from Oct. 16-17 and explore the city virtually until Oct. 31.

Open House Chicago, a free annual public architecture festival, is hosted by the Chicago Architecture Center during October. In 2021, it is a combination of online programs and outdoor tours via the Open House Chicago mobile app and in-person experiences, five of which are in Hyde Park. 

Sinhue Mendoza, the director of communications for the Chicago Architecture Center, said the festival was a celebration of Chicago and a chance to investigate the lesser-known places of the city.

One place Mr. Mendoza recommends is Tree House Humane Society, an eco-friendly cat shelter on the far North Side with 11 colonies and adoptable cats.

“It’s very unique, because architecturally, it’s a beautiful building, and it’s this giant cat rescue that has a cat cafe in it,” Mr. Mendoza said. “It’s kind of like a cat heaven, so it’s a really interesting place that people probably don’t even know exists.”

The Chicago River has world-famous movable suspension bridges, and the McCormick Bridgehouse & Chicago River Museum allows for a deeper understanding of Chicago’s bridges.

“We have the most suspension bridges in the world for a city, and that being said, you’ve probably walked by bridgehouses [in downtown Chicago], and seen them and wondered, ‘Is there someone in there?’ Well, there is someone in there,” Mr. Mendoza said. “One is an actual museum you can visit. You could actually see all the gears and all that from one of the suspension bridges.”