Augustów Canal
It was the first summit level canal in Central Europe to provide a direct link between the two major rivers , Vistula River through the Biebrza River – a tributary of the Narew River , and the Neman River through its tributary – the Czarna Hancza River , and it provided a link with the Black Sea to the south through the Oginski Canal , Daugava River , Berezina Canal and Dnieper River . 
<triplet> Vistula River <subj> Narew River <obj> tributary <triplet> Biebrza River <subj> Narew River <obj> mouth of the watercourse <triplet> Narew River <subj> Biebrza River <obj> tributary <triplet> Neman River <subj> Czarna Hancza River <obj> tributary <triplet> Czarna Hancza River <subj> Neman River <obj> mouth of the watercourse