Having now seen Harry Potter And The Deathly Hallows Part 1 it does in fairness have a couple of standout scenes of the mystical world interacting with the Muggle world - a Star Wars style broomstick chase and battle drops down to earth and carries on along a motorway, and a wand battle in central London - along with long-to-the-point-of-avant-garde periods in isolated wilderness and a chase in a chilly blue-tinged woodland that wouldn't look out of place in Twilight.
Which is another interesting example, viewed from a safe distance. The vampires have divorced themselves from city-based undead society and gone off to a small town in the sticks, keeping their heads down to avoid being smashed to chunks of quartzmeat by the local werefolks. Since it never goes beyond those two monster types AFAIK, the town never needs more areas than a regular small town to contain them credibly.
Unlike, say, Sunnydale, which expanded Springfield-like to become a university town because it needed more room for everything magical and bad to happen there.
Trivia: Twin Peaks has a small-town feel and was apparently originally meant to have a population on its sign of 5,120. This went up by a digit when the show aired, but the town still felt small, despite all the creepiness going on in it, because everybody knew everybody.
When starting a new Buffy PBP, I set it in a semi-real location with a population of 35000. Hopefully, that'll be sufficient.