Drina

The Drina is a 346 km long international river, which forms a large portion of the border between Bosnia and Herzegovina and Serbia. It is the longest tributary of the Sava River and the longest karst river in the Dinaric Alps which belongs to the Danube river watershed. Its name is derived from the Roman name of the river which in turn is derived from Greek .

The Drina is a very fast and cold alpine river, with a very high 175:346 meandering ratio, and relatively clean water, which has particularly intensive green coloration, a usual characteristic of most alpine rivers running through a karstic and flysch terrain made of limestone, underlying the area in which the river carved its bed.

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