Length: 6,8 km.
The ibai-eder reservoir is located in the neighbourhood of Nuarbe in an area belonging to the municipalities of Azpeitia and Beizama. The reservoir caters to 68,000 inhabitants of Urola Medio, Bajo and Costa (Azkoitia, Azpeitia, Zestoa, Zumaia, Getaria, Zarautz and Orio) with an annual consumption of 6,598,000 m³. The reservoir built in 1991 is fed apart from the flow of Ibai-eder and Ibar rivers, by catchment water of a 30 square kilometres area.
Taking the GI-22635 road from Azpeitia towards Beasain, we can reach the Nuarbe reservoir. Leaving the neighbourhood on the left hand side we reach the headwaters of the reservoir which is often confused with the landscape.
The route around the reservoir is flat and has no difficulty, it is accessible to any person. The circular route has a length of 6.8 kilometres, 1.7 kilometres more if the route starts in Nuarbe. Along the route there are wooden benches and a fountain called Itaun located on the bridge that separates the old and the new path.