If you’re not prepared for it, an old photograph of the Twin Towers can do a number on your heart.

That’s partly why Fred Conrad’s picture of the sunbathers is so eerie and disquieting: We know something the sunbathers don’t. Something horrific. Something that will unmake, and remake, the world by the time they reach middle age. Conrad, a former Times staff photographer, took the shot in 1977. It must have seemed whimsical at the time — a nod to the eternal war between business and pleasure. Today, it’s surreal, almost post-apocalyptic. It looks like a poster for “Planet of the Apes.”

And that’s not just because the towers are no more. It’s also because of the beach in the picture. There was a beach in Battery Park City?