Aiviekste

Aiviekste is a river in Latvia. It begins at Lake Lubāns and drains into the Daugava. Aiviekste is the largest tributary of Daugava in Latvia. Aiviekste, along with the Pededze, forms the unofficial border between two historical Latvian regions Vidzeme and Latgale, although the administrative border was slightly different. The river is 114 kilometers long, with annual drainage 1.81 km³.