These posters symbolise rail travel for the1950s, when travel became popular to everyone because it was affordable and such a quicker way of travelling. If you were living in city you could escape to the country or the seaside within a few hours even if just for the weekend.
What I love about these posters is that even though each is done by a different artist they all follow the same style whether they're print or painted. I feel like it's something to do with the line of font along the bottom, even though each of these don't always say 'It's quicker by rail' but since they're still advertising a certain city, then with the symbol for the particular train line, likes them to rail travel. Growing up in south Devon myself I'm mostly taken with the posters advertising somewhere along the coast but that's just me, I love seeing the familiar sights showing that these coastlines haven't changed in the past.