This is one of my favorite SIGNS.  Although the meaning must have been clear to the city government in Barcelona who determined it should be there, I believe there could be several interpretations.

No tourists taking pictures allowed!

So, what exactly is verboten?  The shorts?  The backpack? Socks with sandals?

This sign is in the El Born neighborhood of Barcelona, in an alley behind Santa Maria del Mar church, where there were no tourists (or people of any kind) or interesting sights worthy of a photo.

But, if you see the guy in this SIGN, PLEASE take a picture of him!