Ulzama River

This river originates near the Puerto de Belate and flows south until it reaches its mouth, except for the bend it makes in its upper course to go around Mount Arañoz. While traversing the Ultzama valley, it passes near the towns of Locen, Alcoz, Iráizoz, Lizaso, Cenoz, and Guerendiáin. Shortly after, it receives the Arkil river and enters the Valley of Odieta. It passes through the towns of Latasa, Ripa, Ciaurriz, and Ostiz, where it has just received the Mediano river coming from the Anue Valley. It enters the municipality of Olaibar and crosses near the towns of Bearin, Endériz, and Olave. It continues through the Ezcabarte area and after passing through Sorauren and Oricáin, it enters the Pamplona Basin to flow, shortly after Arre, into the right bank of the Arga river next to Villava.[1]​

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