s through the plains of the
Pannonian Basin. The Kupa originates in Croatia in the mountainous region of
Gorski Kotar, northeast of
Rijeka, in the area of
Risnjak National Park. It flows a few kilometers eastwards, receives the small
Čabranka River from the left, from which point it forms the Slovenian border. It then continues eastwards between the
White Carniola region in the north and
Central Croatia in the south. The Kupa receives influx from the river
Lahinja from the left in
Primostek, passes
Vrbovsko, and eventually detaches from the Slovenian border having passed
Metlika. It then reaches the city of
Karlovac, where it receives influx from two other rivers from the right, the
Dobra and
Korana (which in turn is joined by the
Mrežnica). The Kupa continues flowing to the east, where it merges with the
Glina from the right. It then passes through two small towns called Šišinec and Brkiševina, and then proceeds to the town of
Sisak where it merges with the
Odra from the left and, after passing through Sisak town centre, flows into the Sava. ==Pollution==