Río Biobío
Linguist Robert A. Croese divides Mapudungun into eight dialectal sub-groups (I-VIII). Sub-group I is centered in Arauco Province, Sub-group II is the dialect of Angol, Los Ángeles and the middle and lower Bío Bío River. Sub-group III is centered around Purén. In the areas around Lonquimay, Melipeuco and Allipén River dialect sub-group IV is spoken. Sub-group V is spoken at the coast of Araucanía Region including Queule, Budi Lake and Toltén.