Invisible cities X)

[Airrifle48942]

Hi there, I have noticed something odd with my game. I use world builder to put cities in sometimes, and I noticed that most of these I put turn out invisible! No city name, however double clicking will access the menu and also it's visible as another civilisation. The AI do recognise the city is there (thank gosh), just wondering if this is a bug or if it's intentional?