Michigan has several geographic descriptors that mystify outsiders.
Some are pretty easy to figure out. The "U.P." is the Upper Peninsula, and its inhabitants are "Yoopers." When one speaks of going "north of the bridge," this is the Mackinaw Bridge, which links the two peninsulas together.
There is no "L.P.", however. That's "The Mitten," and everyone is happy to give you directions by pointing on their hand.
The Thumb is an obvious geographic feature, but one of the more ambiguous ones is "up north." This vast expanse is essentially everything north of...something. Typically Lansing, but no one thinks of Flint, Bay City or Saginaw as being really "up north." They're too urban.
Most Michiganders look forward to a weekend or even a day spent "up north," and yesterday the family spent went up to Traverse City and spent the day (and evening) at a resort before returning south. (There is no term for southern Michigan. It's basically not "up north.")
There is something about being there that is simply relaxing. It is rural, filled with natural beauty and things move a little slower.
Which is why we keep coming back.