The UK has an unusual geographic aspect; in common with some other "long" countries such as Norway and Chile, its capital city is far away from parts of the population.
It's sometimes pointed out that the Shetland islands are closer to Oslo than they are to Westminster. In fact, so is Orkney, and the tip of Caithness (John o'Groats).
It turns out that large parts of the UK are closer to another country than it is to Westminster.
This map superimposes a grid on the UK, and colours according to whether the point is closer to Oslo (Norway), Stavanger (Norway), Dubin (Eire) or Westminster.
I used great-circle distances, which are the shortest 'as the crow fly' distances on the sphere (great circles are the routes planes take.. these appear as curves or arcs on Mercator maps)