Gardens:
Boettner Gardens, Milwaukee
International Peace Park, North Dakota

Historic Homes:
Living History Farms, Des Moines
Murphy's Landing, Twin Cities
Dubuque and Galena (so close, don't miss it)
Old World Wisconsin

Other history:
Circus World, Baraboo, Wisconsin
Camp Five, Laona, Wisconsin
Ironworld, USA, Chisholm, Minnesota
Logging Town, Brainerd, Minnesota
Amana Colonies, Iowa (please do NOT confuse the Amansas with the
Amish!)

Pleasant Walks:
State parks along Hiway 61 north of Duluth
Teddy Roosevelt National Park

Historic Homes:
Glensheen Mansion in Duluth, MN
Fairlawn Mansion in Superior, WI

Gooseberry Falls is one of the parks on 61, it's very pretty.

Lief Erikson Rose Gardens and the Lakewalk in Duluth, MN are both very pretty.

There's also the Sculpture Garden in Minneapolis, MN.

Minneapolis has a beautiful chain of lakes with walking paths around them, and many of the houses that can be seen from the paths are lovely. The Lake Harriet rose garden and the peace garden are also adjacent to the Lake Harriet path.

St. Paul's Summit Av. is on the Natl. Historic Register for its wide variety of historic homes. They can ony be observed from the outside with the exception of a few like the James J. Hill house. It is great for an afternoon walk as is the very close area along both the Minneapolis and St. Paul sides of the Mississipi River. There are nice walks with interesting old house to see as you stroll along the dedicated walking paths.

AS mentioned above, MN's North Shore along Lake Superior is one of the country's 10 most scenic drives, and there are lost of great state parks one can walk in. We like to stay in Naniboujou Lodge north of Grand Marais. It is a lodge that was built for wealthy investors just before the 1929 crash. The building is very different, it is in a great location on the lake, and the food is good. If you are someone who needs a huge room though, this is not the place. If you are the type of people who are fine spending an evening in the lodge's common areas with book in hand or sitting outside admiring the lake, it is a great place.

Honestly, as a pretty much life long MN resident, your best bets are MN and Wisc. As far as I am concerned, with the exception of the Medora area with the Theodore Roosevelt park which is on the very far western side of ND, there is nothing in ND. And it is a very looooooog drive through nothing interesting to get there. Our kids went to college in Iowa, so on trips down there to visit we stopped in the Living History Farms and the Amana colonies. I wouldn't make a special drive through Iowa just to go to those places.

Wisconsin has some interesting places in the area just west of Madison that make for intriguing stops--Mineral Point and the Frank Lloyd Wright areas. Have you thought about Door County in Wisonsin at all? It is not exactly what you are describing, but it is a very, very nice place to visit.

Have fun.

Madison - Olbrich Gardens, UW Arboretum, walk out to Picnic Point

Frank Lloyd Wright's Taliesin in Spring Green.

Lots of historic homes in Minneapolis/St. Paul and the rest of the state: http://www.mnhs.org/visit/

I'm sure the other states have a similar historical society.

If you're a fan of Laura Ingalls Wilder or Little House on the Prairie there are some sites scattered about the area as well.

Apostle Islands and Bayfield. We took a sightseeing-type ferry out to the islands, got off at one, and were amazed to see big waves rolling in. Whitefish livers were a local delicacy - so we decided to try them - yum! (We do like chicken livers - these were less liver-y tasting). We stayed at a lodge a bit out of Bayfield and went fishing with a guide - that was fun, too.

You're right..there's nothing in North Dakota. No traffic jams, no miles of suburbs, no smog, no long waits for restaurant tables, no-one to ignore you when you need help, etc. Only miles of prairie (interesting if you've never seen it, by the way), relaxing drives (get off the interstate!), fresh air, bright skies/brighter stars, peaceful walks. Historic homes - Custer House & Earthen Mandan Indian Village at Ft. Lincoln State Park (Bismarck/Mandan) - Chateau De Mores Home & Badlands (Medora) - Stutsman Co. Museum/House & Frontier Village (Jamestown) - Bonanzaville (Fargo). Gentle walks - basically, anywhere you'd like to stop your car and look around. Numerous State Parks to choose from!

I am going to defend my home state like HotWheels. There are plenty of things to see in Iowa.

Ames--is home to Iowa State University, which IMHO has the most beautiful campus in the US. Next to the Footbal stadium is the Reiman Gardens. The site also has a butterfly house.

Cedar Rapids-- Brucemore a Queen Anne style mansion on a large estate. The gardens have roses many flowering perennials. In the summer they have outdoor concerts, Shakespeare on the lawn and much more. The house used to be owned by the family that started Quaker Oats.

Check out ilovegardens/iowa.com for many more.

Iowa may not have a National Park, but it has many well maintained state and county parks.

The river drive along the Mississippi is hard to beat.

Every state in the MIDWEST has ALOt to offer

In St. Paul is the Science Museum (www.smm.org) with the Historic St. Paul Hotel a couple of block away. King Tuts treasures are at the museum currently. The Minneapolis Institute Of Arts(www.moa.org) is worth a look, and free. The town of New Ulm has a lot of unique homes and a brewery, the town is situated on the Minnesota River. I second julies north shore and Naniboujou Lodge suggestions. www.exploreminnesota.com for more ideas.

oops, wrong link www.artsmia.org for Minneapolis Institute of Arts. moa might be the mall of america. James J. Hill House is in St. Paul www.mnhs.org/hillhouse. Walker Art Center, www.walkerart.org Wolfgang Puck has a restaurant there called 2021, a good spot for lunch.

Milwaukee Avenue Historic district between Franklin and 24th Street Mpls and Irvine Park Historic District off West 7th Street St paul, The Arboretum in Bloomington is beautiful.

MaryAnn: during what month(s) will you be taking this trip?

Another poster traveled to Iowa last summer and I recommended several places that she and her daughter said they enjoyed - much the same as what you're looking for.

Here's a link to that thread:

http://www.fodors.com/community/united-states/iowa-amana-colonies-lodging.cfm

As PaulRabe mentioned, you would likely very much enjoy the Amana Colonies, which are not to be confused with the large Amish community in the town of Kalona, which is not terribly far from the Amanas.

Kalona itself is a nice little place to visit - a very small town, with a couple of nice restaurants and lots of little Amish shops, along with a historical Amish farm.

In SW Wisconsin, for historic homes, Villa Loius, Old World Wisconsin, Pendarvis, and Mineral Point in general. In Milwaukee, the Pabst Mansion is a must.

Gardens in the Milwaukee area: Boerner Botanical Gardens, Mitchell Park Domes (Conservatory), Schlitz Audubon Nature Center.

In Wisconsin, almost every state park (and there are a lot of them) has a beautiful nature trail. Last summer we enjoyed Governor Dodge State Park. Our favorite is Devil's Lake.