salland is bound to the west by the provincial border with gelderland, which is partly formed by river ijssel; to the north by the meppelerdiep stream and the provincial border with drenthe, which partly consists of the reest stream; to the east by the borders with the german state of lower saxony and the eastern overijssel region of twente; and to the south by the border with the gelderland region of achterhoek, part of which is formed by the schipbeek stream.