Translation:The river next to the city is very long.
Is this the same as saying "A város melletti folyó nagyon hosszú" or is there some difference between them?
I guess it is the same when talking about the length of it. It it were the width or depth, one could wonder if it is the river identified as the one next to the city, or if it is next to the city where the river is wide/deep. To differentiate between the two, Hungarian can say "a város melletti folyó" - the river that is next to the city.