Zegama's main characteristic is its natural location as the last Gipuzkoan town up the valley of river Oria, very close to the Aizkorri-Aratz Natural Park, in which the highest mountain in the Basque Autonomous Community can be found, the popular Aizkorri summit (1,528 m), located at the same name mountain range towering over the whole area. The Oria river, the longest one in the province of Gipuzkoa, rises in several springs and their corresponding streams flowing down the dramatic slopes of the valley that merge in a main stream before the nucleus of the town. The southern Otzaurte hamlet (IPA: /o'tsaurte/) stands on the dividing line of the waters running onto the Mediterranean watershed and those flowing north to the Atlantic through the Oria river.