And a land border with Denmark. https://en.wikipedia.org/wiki/Hans_Island https://en.wikipedia.org/wiki/Hans_Island Also, I think the constraint to be in the

And a land border with Denmark. https://en.wikipedia.org/wiki/Hans_Island https://en.wikipedia.org/wiki/Hans_Island Also, I think the constraint to be in the EU is that it has to be "an European country". It's relatively vague.