You can generally assume around here that public parks are ok. There are some exeptions of course. I've also never had problems with public schools (just go in non-school hours). I asked at one in particular (East Clinton in Huntsville) and was given permission.
If in doubt, its pretty easy to ask someone. I was in Cullman at Sportsman's Park last week and asked at the store there. Took about a minute for the lady working there to call the park manager and it was cool.
I've detected in Scottsboro once. You might also try Gurley. The elementary school there has revealed a few wheaties for me, so there might be some silver lurking.
Holler for more specifics.
*oh yeah, what detector did you get?
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