Most of Ukraine's rivers belong to the Black and Azov Sea basins. Ukraine's rivers are predominantly flat, with winding channels. They glide slowly through wide valleys. Rivers flowing off the Carpathian and Crimean Mountains are narrow, rapid and shallow. There are few rivers in the southern regions of Ukraine.
Navigable rivers are important for transport.
The Dnipro's largest tributaries are the Prypiat and Desna. Another major river is the Dnister. Originating in the Carpathian Mountains, it flows along the border of Ukraine and Moldova, empty-ing into the Black Sea. It floods not only in spring, but also in summer after heavy rainfalls. Its largest tributaries are the Stryi and Zbruch.