Blue Sky Directly Overhead but ...

It would be fair to write that Antwerp city struggles with terrible air pollution.  Most of Europe drives through Belgium ... trucks in their gazillions.  People on their way some place else.

I read: Antwerp is particularly affected by air pollution generated by the eight-lane motorway passing near the city centre, its important seaport (second largest in Europe), as well as by the presence of the second largest petrochemical industry worldwide. Moreover, the high buildings located in the city centre create street canyons where noise and pollutants are especially concentrated.

Researching this was fairly depressing ...