A view of the residential buildings and grass-covered wharf of the Oder River. The Oder is a river in Central Europe. It is Poland's second-longest river in total length. The Oder rises in the Czech Republic and flows 741 kilometers through western Poland. The river is an important waterway, navigable throughout most of its length. It forms a link, by way of the Gliwice Canal, between the great industrialized areas of Silesia in southwestern Poland, and the trade routes of the Baltic Sea. (Photo by Karol Serewis / SOPA Images/Sipa USA)