Joint Danube Survey 4 – the biggest international river expedition of the year is coming soon

In June 2019 on the Danube Day will start the biggest international river expedition of the year Joint Danube Survey 4 (JDS4). Joint Danube Surveys are organised by Secretariat of the the International Commission for the Protection of the Danube River (ICPDR) Three Joint Danube Surveys were previously conducted in 2001, 2007, and 2013.