You can access the Art Institute by a long ramp from Millenium Park.Have lunch at the Museum's Terzo Piano, very ggod food and a nice light filled space in the Renzo Piano designed new wing.

Today I was googling the artist Marsden Hartley. That made me want to go to the Art Institute. It's already been very high on my list of art musuems. It sounds like an amazing musuem.

Again, thanks for the comments and recommendations which are much appreciated.

First, a big "yes" to the Art Institute. Now, there's a lot to see there; so if you have any interest in it, they have audio tours of the highlights of the museum, as well as guided tours (look at their calendar online) for those with limited time.

Although you can indeed spend an entire day there, in your case, I feel it might be overkill. Especially in the summer, if the weather is pleasant.

My suggestions:

At the base of the Willis Tower (across the Chicago River from Union Station), you can pick up Shoreline's water taxi to the DuSable Bridge (fka Michigan Avenue Bridge). I'm suggesting this not only for the view but for the time savings over CTA bus.

If you have the time and inclination, I'd recommend taking the Chicago Architecture Foundation's River Cruise - where you'll learn about all those buildings you've just passed on the north and south branches of the Chicago River (plus more). Their boarding area is on the River Walk at the southeast corner of the DuSable Bridge. You'll see the blue awning.

Speaking of the River Walk, it's really nice to just stroll along, stopping from time to time to view the River traffic.

Millennium Park is three blocks to the south of the Chicago River on Michigan Avenue. Right across the street is the Chicago Cultural Center, where you can take one of the FREE InstaGreeter tours of the Loop. You don't have to reserve, only show up.

As I mentioned, Millennium Park is right across Michigan Avenue. The Frank Gehry-designed Pritzker Pavilion is where the Grant Park Music Festival performs, as well as the Downtown Sounds festival. If you take a look at the former's calendar, you will see that they have open rehearsals during the day, when their performances are in the evening.

If you were interested, the Chicago Architecture Foundation's ArchiCenter is across the street from the south end of the Art Institute in the Santa Fe Building. You might wish to view the Chicago Model City.

Dang it. I wanted to post some links and mention one other thing:
www.shorelinesightseeing.com/watertaxis.html
www.architecture.org
chicagogreeter.com
www.chicagomodelcity.org
www.grantparkmusicfestival.com

The Bridgehouse and Chicago River Museum is at the DuSable Bridge. Even if you don't care to stop in (and I hope you do), look at their website, as well as that of the docent mentioned in the Bridge Lift section. bridgehousemuseum.org/home

My purpose for mentioning these other options is not to distract from your original purpose of visiting the Art Institute (of which I highly recommend). And I wanted to give you a number of them.

I just noticed an error in my first post. With the Shoreline water taxi, you are on the MAIN and south branches of the Chicago River. My apologies

We lived in Chicago for 20 years and if I had only one day, it would be the Art Institute. IIRC, summer should be a terrific time to have lunch outside, they do a very nice job and it's lovely.

If you go, please think of me. It's one of my fondest memories of when my children were young and we spent Saturday mornings there at their free children's art classes. We often splurged in the summer for lunch outside. Their collection of Impressionist art, if you are into it, is lovely and lots of other interesting stuff to see. Have fun!

I've just posted a question on this board and this thread is already giving me some great ideas...