Kortezubi offers superb examples of Biscayan Basque farmhouses. In the district of Oma we can find converted farmhouses of the Gothic era, from the 15th and 16th centuries, such as the farmhouses Olakoa and Beaskoetxe, although the only identifiable feature as being from that era is their side entrances.

Etxebarria farmhouse

The farmhouse of posts was developed throughout the 17th century and they can be seen in the large number of these new style farmhouses in Bizkaia brought about by the increase in corn growing and the gradual ploughing of new land for agriculture. The farmhouse, Zierre, in Oma dates from this period and is one of the best examples of this type of rural construction. Another interesting farmhouse is Urriene, one of the oldest in the municipality and the region. Other interesting farmhouses are Kurtziñe, Sakona and Barrutibasobekoa, among others.

The farmhouse without posts gradually replaced its predecessor by the middle of the 18th century. In this type of farmhouse, stone played a supreme role in contrast to wood which was becoming scarce and expensive. Noteworthy, in this style, are the farmhouses: Mendoza, Basozabal, Omabeiti, Orriano and Solozabal.

There are outstanding examples of the farmhouse without an arch in the Oma Valley and, of all of them special mention must be made of the Omagogeaskoa farmhouse, noted for the quality of its stonework, the combination of materials and the preservation of the original building. This type of farmhouse incorporates the arch in the portico, substituting the lintel, placing the whole weight of the building on the jambs. Other farmhouses in this style and which are worthy of mention are Lezika and Andikoetxe.