Explaining the why takes more time, but only because there are so many reasons.
Cheese
is one. Wisconsin makes over 600 varieties, which is more than France, though it's doubtful the Frogs would deign to recognise one of the favourites. Cheese curds, crumbed and deep-fried, are a guilty indulgence that's irresistible in a cosy restaurant with a glass of draught Spotted Cow.
It may sound like a McSnack, but Wisconsonites - Cheeseheads - insist the curds must be so freshly made they squeak when bitten into. They also use cheese brine, a waste product, to de-ice their roads in winter.
It was an especially harsh winter this year, and, in April, there was still ice on the lakes, tinkling musically as the surface broke up.
Wisconsin claims to have water everywhere, and its thousands of lakes, surrounded by woodland, are popular retreats from Chicago's oppressive summers.
Lake Geneva is one, its shores dotted with millionaires' mansions, wooden beauties over a century old with turrets and verandas, owned by families with famous names like Wrigley, Selfridge, Sears and Maytag.
In the town is an appealing hands-on museum, staffed by enthusiastic docents with great stories - the one about the origin of sundaes involves lithium and cocaine - and on the waterfront, near an unlikely sandy beach with lifeguard tower, is Baker House.
An elegant summer home from 1885, it's now a restaurant filled with hats from the 1920s, which guests may wear as they're served by waitresses in lace-trimmed pantaloons.
A Wisconsin speciality - deep-fried cheese curds. Photo / Thinkstock
Architecture is another of Wisconsin's prides, its most famous son, Frank Lloyd Wright.
State capital Madison, prettily positioned on an isthmus between two more lakes, has an elegant event centre, Monona Terrace, on the shore of one of them built to his design. It's a splendid place, curvaceous and airy, a fitting counterbalance to the nearby classical Capitol building, which is identical to, but just a little smaller than, the one in DC.
Out in the hills is Taliesin, Wright's own home, a thoughtful place of stone and glass, fitted into the contours of its site, and made to measure. Literally: Wright considered his height, 5 feet 8 inches, to be ideal. Anyone over six feet was "a waste of material", so tall people visiting the house have to be prepared to duck through doorways.
A stained glass window at Frank Lloyd Wright's house. Photo / Pamela Wade
Wisconsin's most idiosyncratic building, though, has to be the plainly-named House on the Rock, 60km from Madison. Rising out of the trees, its angled roofs perched over a high outcrop give no clue to the astonishing marvels inside.
Built by eccentric Alex Jordan to house his collections, it just grew as he indulged his whims over 30 years. Inside, narrow corridors follow the rock contours that form some of the walls. The floors are uneven and the light dim, but there's no tripping because there's so much to look at that a slow shuffle is the usual pace.
Spotlit in grottos and caverns are collections: stained-glass lamps, dolls, musical instruments, guns, tools, toys, dishes, crowns, ornaments. There's colour, music, shagpile carpet and around every corner a new, bizarre surprise, such as the Infinity Room projecting 66m, unsupported, high above the forest.
Then there's the carousel. It's the world's biggest indoors: 269 animals, 182 chandeliers, 20,000 lights, and it still works, pumping out its jangly tune while various bits swoop and spin. For us, it was the climax of the visit, but then we didn't have time for the galleries of cars, planes, boats, dolls' houses or the 60m sea monster. It was like Disneyland on acid, and it made us feel like children again.
More grown-up toys are on show in Milwaukee. Here is the Pabst Brewery for those who like to bend their elbow; and the Pabst Mansion for more refined tastes.
The Public Market is full of tempting delicacies, and the city's restaurants include a chrome-and-vinyl 50s diner with a great line in pie and pi puns.
On the shore of Lake Michigan is the remarkable Milwaukee Art Museum with a roof that opens like the wings of a swan, while on the other side of town the Harley-Davidson Museum recounts the motorcycle's story from the backyard shed to the vast factory, from 1911's motorised bicycle to the latest power-assisted model, with everything between from camouflage to rhinestones.
There ought to be a third question: "Can I come too?"
CHECKLIST
Getting there: Air New Zealand flies daily to Los Angeles and San Francisco, from where local carriers connect to Chicago or Milwaukee.
Further information: See travelwisconsin.com and DiscoverAmerica.com for more on visiting Wisconsin.
