The series is set in Westchester County, New York, but the scenery and vegetation betray that it was filmed in other than the northeastern US, especially in long shots showing terrain uncommon in that area.
The admission process into Miracle is deeply flawed. Anyone who has a certain wristband gets in, period. No fingerprint matches? No DNA? No attempts at all to match the person flashing the wristband to the banded person? No.