Just a guess but:
The sun and the water is probably there because the sunset on Lake Shinji (along the train line) is really famous in Japan (and gorgeous by the way).
The white and black symbol in the bottom left is the roof of a Shinto Shrine in Izumo Taisha, the white and blue "ghosts" are maybe just clouds because the name "Izumo" is written using the kanji (ideogram) for "cloud". and the smiley faces because... it's Japan!
I might be wrong, but this is how I get it.