The Zuia valley is covered by a fine oak wood which runs along the river Baias from Murgia and Ametzaga to Lukiano and Gilierna, where it extends into the municipality of Urkabustaiz through Abornikano. From the villages along the way trails lead off into the woods, which provide a habitat for a huge variety of birds, small amphibians and reptiles.

In the direction of Aperregi, Domaikia and Jugo the oak woods become dotted with gall oaks, durmast oaks and beech trees, especially on the slopes of Oro and the Sierra de Badaia hills.
The river Baias runs through the middle of these woods and into Urkabustaiz at Lukiano. The five kilometre stretch between these two municipalities is one of the finest fishing areas in the province. On the frontier between the municipalities stand the ruins of the La Encontrada iron works, which takes its name from an old local legend.