As a part of project Integra, Centre for Peace, nonviolence and human rights presented a comparison of the longest rivers in Syria and Croatia.

The Euphrates River is the longest and most historically significant river in Syria and Western Asia covering a distance of 2.800 km. It is one of the two rivers of Mesopotamia with the other being Tigris River. It flows from the confluence of Kara Su and Murat Su in the town of Keban in Turkey. The two rivers combine into the Euphrates at the Keban Dam which then flows to Turkish-Syrian border. Most of the waters of the Euphrates River are from the rainfall and melting snow. Three rivers empty into the Euphrates; Sajur, Balikh, and Khabur. The Euphrates drains an area of 223,674 square miles with the greater part of the Euphrates basin located in Syria, Turkey, and Iraq. The river is a major source of water for most households living along its banks. It is also an important source of fish and water for irrigation. The Euphrates also supports natural vegetation growing along its banks.

The Danube River, at 2.850 km, is the second longest river in Europe and the longest that passes through Croatia. This river flows through 10 countries before emptying into the Black Sea and the Danube Basin takes up approximately 62% of the area of Croatia. The lower areas of this basin are filled with fertile soil and, therefore, have a higher population density than the upper regions which are covered in forests. The river provides hydroelectric power to the surrounding communities and carries the majority of traded goods to inland areas. Some wastewater is discharged into this waterway, most of which has been treated. The wetlands within the basin are home to around 250 bird species, 79 of which are considered endangered on a European level. One of the most important breeding grounds for carp, a fish species, is located here as well. Riparian woodlands surround the basin and are home to Slavonian oak trees. Environmental threats to the river and its basin include urban development, tourism, agricultural runoff, industrial pollutants, and fishing. In 1998, the International Commission for the Protection of the Danube River was established in order to promote sustainable water use practices and to conserve its biodiversity.