This is a great contemporary art museum that is free to explore. It is open 24 hours a day to the public since it is embedded as a part of a hotel.
This is one of three Starbucks Roasteries in the United States. It has five unique floors with a nice rooftop terrace. It offers light meal and snack options in addition to coffee flights, cocktails, and unique drinks. It is the least crowded in the evenings and great for a night cap. Highly recommend if you have not been before.
This is a great brewery with flights of house brewed beers for you to try. The burgers are a good choice.
There are many architecture cruises in Chicago. September will be a beautiful time to explore the riverwalk - which trails from the navy pier area west and south for ~1.5 miles. There are various restaurants, bars, wineries, and dessert options on the river.
This beach is just off Michigan Avenue between Oak & Division if you would like to sit by the water and relax. The Chicago waterfront has sand beach areas and concrete seawall areas which are nice for a walking trail. This is a nice “city beach” with views of the skyline to the west of the water.
This is a beautiful location for Sunday brunch if you wanted to eat somewhere scenic before leaving town. Reservations are needed. This is located in a pretty courtyard within the upscale Restoration Hardware furniture store.
This is the observation deck at what was formerly known as the John Hancock Building. If you are not interested in the full observation deck experience but still wanted to catch some great views, I would highly recommend visiting the Signature Lounge on the 96th floor where you can have a drink and and catch some views. https://www.signatureroom.com/lounge/
If you have the time, Chinatown is always a great place to visit. It is accessible by both the Red Line (towards 95th), drive south on Clark Street to Archer, or you can take the Chicago Water Taxi from the loop to Ping Tom Park in Chinatown (cool way to get on the river without doing an architecture tour). Our favorite places to eat in Chinatown are Golden Bull, Strings, Sushi Plus, Chi Cafe, Ming Hin, Hing Kee and if you enjoy some spice try Yao Yao. There are a bunch of delicious boba shops (the most popular being Joy Yee) and dessert shops (i.e. MatchaEn/MangoMango/Joy Yee Plus/Tous Les Jour). We recommend matcha soft serve ice cream at “MatchaEn”
Wells Street is great to check out in the summer. It's lively with a number of bars, restaurants, and has a number of interesting boutiques. I am just listing a boutique I enjoy in Old Town to give you an idea of the general area, but this is a great reprieve from Michigan Avenue if you want something more quaint and charming.
On Michigan Ave just north of Chicago Ave is Water Tower Place, a seven story shopping mall with a small food court. It features a Harry Potter “Magic at Play” exhibit and store.