The Serra de Artxuga, Zarikieta and Montes de Areta Nature Conservation Area (ZEC) is located in northeastern Navarre and comprises the group of inland pre-Pyrenean mountain ranges located between the Salazar and Urrobi rivers. These habitats are preserved for hygrophilous sedges, forming part of mosaics with peaty zones of great conservation value. The Urrobi and Irati rivers are the two main channels that flow into the area, although they do so through dammed waters, giving rise to the Itoiz reservoir. However, a large number of streams and ravines flow into the Irati and Urrobi rivers in the western sector, the Areta river in the central sector, and the Salazar river in the eastern sector.
This area is notable for its abundance of limestone, dolomite, marl, sandstone, and flysch. The erosion of these materials has generated escarpments, ridges, and a notable karst development with sinkholes, lapiazes, or pits, and small caves. Of particular note are the Oroz-Betelu massif and the Mount Baigura area.