I've been asked if this poster is meant to be melancholy. My response is- "only if you want it to be".
Taking one last look doesn't always have to be a sad experience. It can be your last look as you leave a town you've been aching to get out of, your last look before beginning an adventure, the last look before taking a big step towards something you want. It's really more about the beautiful moment just before things change. One can see change as scary or precipitating loss- or you can see it for what it is, simply part of the unavoidable cycle of life.