Translation:Rotterdam had the biggest harbor in Europe.
yeah, I think they wanted to say "of the world", which it was until 2002.
Is "greatest" a good translation of grootste, or how would one say that? Also, greatest can mean biggest.
In this case "largest" or "biggest" is the better translation for "grootste", as the sentence describes the size of the harbor. "greatest" points more to the splendor or grandeur of something, although in Dutch "grootste" can point out both size and splendor.