The City of Barcelona has a Visitors Book on their website, with the following disclaimer:
You may write your message on the city of Barcelona or on this Website with no limitations except the usual ones of courtesy and democratic respect. This means that messages that contain expressions that are offensive to human dignity, that are racist or xenophobic, that advocate or induce violence or illegal activities, or that violate the principles of democratic harmony will be deleted.
If you’re going to limit expression, this seems like a very well-worded way to do so. I like the notion that courtesy and democratic respect are considered simply “the usual ones.”
Robert is advocating that Barcelona become the centre of our European vacation.