The 45×90 points, as they're called, are the four points on Earth which are halfway between the geographical poles, the equator, the Prime Meridian, and the 180th meridian. That's why some sources state that these points are considered "The Center Of The World". Only two of these points are on land - the other two fall in the middle of the ocean. And the one not in Wisconsin is in a desolate, mountainous region of China near Mongolia that's very difficult to visit. But this one you can visit. There is even a statue.
Source: Only in your state