Do they really have brilliant blue lampposts?

The colours here are as were; it was a festival day of some sort and there were coloured lights along the riverside. This was taken from the sun deck of the (moving) boat, hence image quality not great.

Bellos reflejos.

It's a nice shot: I'm just puzzled that the lamp POSTS appear to be bright blue or green.

It's banks of coloured (probably LED) lights fixed to them, rather than the lamp posts themselves. And they're only in that riverside plaza near the mosque, where there was (I think) a funfair, not across the whole town.

wonderful