context: Coordinates: Sava (Sava) (Serbian, Croatian, Bosnian, and Slovenian: Sava) is a river that runs through Slovenia, Croatia, Bosnia and Herzegovina, and Serbia. [1] [2] [3] It is considered one of the tributaries of the Danube where it empties in the Serbian capital Belgrade. Its length is 940 km and its water surface area is about 95,720 km. In the Roman era it was called the Savus. It is often considered the northern border of the Balkans.
question: Where does the Saga River flow?
answers.text: Belgrade