The Drava River is the fourth largest and fourth longest Danube tributary Rising in Italy, it drains the Southern side of the Alps to the Danube and the Black Sea. The Drava is 719 kilometres long, and flows through Austria, Slovenia and Croatia, where it forms the border between Croatia and Hungary, before heading back into Croatia again to meet the Danube near Osijek, where it is 320 metres wide.
Along the upper reaches, above Donja Dubrava in Croatia (before its confluence with the Mura), more than 20 dams have been constructed to harness the powerful volumes of water to generate hydroelectricity.
Like most lowland rivers in Europe, the lower Drava has been considerably regulated, especially downstream of Barcs, with embankments and channels to direct its flow. In spite of these changes, natural habitats along the middle and lower reaches of the river host unique assemblages of flora and fauna, and several endemic species.
Efforts are under way to establish an International Biosphere Reserve along the Drava involving four all countries sharing the river basin.
ICPDR Danube Watch: The Danube-Black Sea clean-up story
Maribor, 24 September 2008. A “Declaration concerning common approaches to water management, flood protection, hydropower utilization and nature and biodiversity conservation in the Drava River Basin” was adopted by Participants at the “Drava River Vision Symposium” in Maribor, Slovenia.