For me, the “song of summer” is the same every year: “My War” by Black Flag. Just kidding. I don’t have a personal song of summer, and I typically have no idea what the song of summer is for everybody else either until much later, when I read people referring back nostalgically to whatever they thought it was. I don’t listen to the radio and don’t have much exposure to anyone who listens to current music. The main place I hear pop music is in stores, so for me, the songs are all about shopping.
Jusqu'au septembre's been a Swann-song phrase for me for a few decades. If nostalgia serves, it was also a movie that included s.o.s. (song of s...) ingredients such as girls, French, lez action, you name it. As to Sumer in your pic there, let me just say that any good iron age needs a bronze predecessor to have golden feelings for. I always forget that in the onward-and-upward tales of civilization, the period named for drab metal comes after the period named for golden metal. Is that iron or irony? [I always get those mixed up.] True fact about me: till the age of reason, I lived in Golden, Colorado, where I'm told I fleeted the days in such careless pursuits as throwing rocks at cars while Ma worked at the registry of motor vehicles. And they say there was no golden age. Sumer is summer in summary form, no sooner summarized than gone. Sumer is the golden age of us all. Gilgamesh was our father. If he wasn't, we'd have to invent him.