The Urdaibai estuary is a natural region anda Biosphere Reserve of Biscay, Basque Country. It is also referred asMundaka or Gernika estuary, situated at 45km. from Bilbao. Urdaibai is located on theBay of Biscay coast, in the north of the Iberian Peninsula. Urdaibai covers an area of 220 km2 (85 sq mi) with some 45,000 inhabitants, most of them concentrated in the towns ofBermeo and Gerkika. The te…