I have a cars website where a single item (a car) is found with this url syntax:
but since every car has a unique ID I didn't differentiate it with cities,
in other words cities don't work as categories,
in other words
hostname.it/car/rome/4566 and hostname.it/car/milan/4566
return the same car, the same applies to non-existing cities like
However the right url is only one, the one with the city where the car actually is.
So if in my sitemap for each ID (for each car) there is only one url I would like to know if this is bad for SEO, and results in lower ranking.