Brandenburg is bordered by Mecklenburg-Vorpommern in the north, Poland in the east, the Free State of Saxony in the south, Saxony-Anhalt in the west, and Lower Saxony in the northwest. The Oder River forms a part of the eastern border, the Elbe River a portion of the western border. The main rivers in the state itself are the Spree and the Havel. In the southeast, there is a wetlands region called the Spreewald; it is the northernmost part of Lusatia, where the Sorbs, a Slavic people, still live. These areas are bilingual, i.e., German and Sorbian are both used.