Vale do Javari is one of the largest indigenous territories in Brazil, encompassing 85,444.82 km2 (32,990 mi2) – an area larger than Austria. It is named after the Javari River, the most important river of the region, which since 1851 has formed the border with Peru. It includes much of the Atalaia do Norte municipality as well as adjacent territories in the western section of Amazonas state. Besides the Javari it is transected by the Pardo, Quixito, Itaquai and Ituí rivers.