It would be nice if, somewhere in the story, we could be told where this is.
The Map shows it just north of Milwaukee.
It's in southeastern Wisconsin, just outside of Milwaukee.
Please see my post, no. 15. I lived in the Milwaukee area for almost 13 years before I moved to Knoxville, TN about 18 years ago.
It's in a little town called Erin, just outside of Hartford, which is a little north of Milwaukee. Nice, peaceful, rural area, near the Kettle Morain (I think). You can see Holy Hill from miles away in several directions because it is on a very high hill.