St. Louis Missouri is a wonderful place to visit as well. We have many fun things for the family (St. Louis Zoo - voted one of the best) a cool place called City Museum which is more of a playground for children and adults alike than a museum. We have 6-flags over mid-america which is approximately 30 minutes from downtown St.Louis. Also there are several wineries with bed and breakfasts. We have upscale nightclubs (think New York of Las Vegas) and a wonderful historical district called Soulard which has a ton of great blues bars. Of course, there is the arch. We have "the landing" which is similar to Bourbon Street, but you can't take your drinks out of the bars. If that doesn't suit your needs, there are beautiful rivers for canoeing or rafting, horseback riding. St. Louis and its surrounding areas have what I believe to be a good variety of city life, family activities, and nature.

I almost forgot, we have water sports, snow skiing / boarding, and golf as well.

You didn't say which area you are thinking about...as you see from the other comments, the midwest is a huge area. If you are driving along I-70, you pass through both St. Louis and Kansas City. Lewis and Clark Expedition is represented in both areas. St. Charles, along the river between the 2 cities, is a great example of the old river towns which were created due to the steamboats, and was influenced by the French. Kansas City has the country's best WWI museum at Liberty Memorial, The Plaza, a downtown-upscale community, built to resemble Seville, Spain, because it is the sister city of KC. You can watch real Pro Sports: football, baseball, soccer, race cars etc... learn about the cattle drives, poney express started from Kansas City, most of the famous "trails west" started in either St. Louis or KC, so YES, go there. It is a slice of the more "authentic" look at America, not the tourist trap. Also, there are wonderful Lakes....Lake of the Ozarks and Table Lake are huge. Get on the internet and have all these places send you brochures.