In the background we see a passenger ferry - I'd guess it is en route to Stockholm, Sweden. Even tough the Baltic Sea isn't that vast, it still has this magical charm of the sea; a salty feeling in the sea wind, and the call of the distant shores - pass through the straits of Denmark and from there on you could sail all the oceans of the world.

(In a way, The Earth should actually be called The Ocean, as continents are just islands embraced by the waters of the world. Oh well, what I mean is this adventurous sense of 'no limits' - that theoretically speaking one could sail anywhere, reach any shore of the world.)