Restoration of the Oka River’s upper estuary, part of the Urdaibai Biosphere Reserve
The estuary of the Oka River is located within the Urdaibai Biosphere Reserve, on the coast of Biscay, Basque Country, north of Spain. It is an area of high ecological value. Its landscape has been transformed over the years by human activities, as it has been inhabited since Prehistoric times. The most important activities affecting the landscape of the estuary have been agriculture, cattle rising and a shipyard. While the first two have practically disappeared, the shipyard activity is still on-going, although with less intensity than in previous decades.