All around me the snow lay smooth as Christmas cake icing. The surface was cracked only by the metallic shimmer of a frigid river. I stared at my phone, transfixed, as a blinking circle traversed the dotted line stitched across the map. I had crossed the Arctic Circle – the invisible halo of latitude that crowns the northern fringes of Russia, Canada, USA, Greenland, Iceland, Finland, Norway and Sweden, as if a school compass had been swizzled around the top of the Earth.
I looked around me, waiting for the fanfare. The spotless carriage of the Nordland train, bound for Bodø, was empty save for a lone man whose head was burrowed inside a book. The words, ‘We are soon crossing the Arctic Circle,’ still blinked silently across the train's…