Sava

The Sava is a river in Southeast Europe, a right side tributary of the Danube river discharging in Belgrade. It is 990 kilometres (615 miles) long, including 45-kilometre (28 mi) Sava Dolinka headwater rising in Zelenci Pools near Podkoren, Slovenia - draining the second largest catchment among Danube tributaries after Tisza and covering 97,713 square kilometres (37,727 square miles) of surface area. It flows through Slovenia, Croatia, along the northern border of Bosnia-Herzegovina, and through Serbia. Its central part is a natural border of Bosnia-Herzegovina and Croatia. Sava is considered to be the northern border of the Balkan Peninsula.