It flows into the Caspian Sea. Its the largest river in Europe.
It flows into the Caspian Sea
There are numerous ways to compare rivers - by their differences, by their similarities and some of the criteria would be - length, discharge, size, sources, mouth, basin, tributaries, area through...
The Volga is longer at 3692 km in length. The Danube is 2860 km.
Not so sure, but most things I have heard is because it is the longest.
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