What to do on a hot summer day? We have here 36°C (97 F) here today.
My suggestion is to take your wife or girl friend and drive to the next air conditioned shopping mall. Buy the next birthday presents you need, maybe a little gift for a friend, enjoy some gelato and just look around
We drove today to the Löhr Center in Koblenz (140 shops).
And now enjoy the soccer game: Argentina against Germany