Engineers Dabit Zabala and Arkaitz Gabantxo are the hasiberriak —a Basque word meaning newcomers— behind  a small wine-making project they stared in 2017, initially as a hobby, in the Urdaibai region of DO Bizkaiko Txakolina.

The catalyst was the death of Dabit’s father in 2016, who left behind a vineyard in Mendata, on the right bank of the River Oka. Gabantxo also had the opportunity to acquire a neglected plot in Errigoiti, on the opposite slope of the valley. These two sites offer markedly different grapes: structured, riper fruit in Mendata, with loamy soils over slate bedrock, and acidity and freshness in Errigoiti, thanks to its higher elevation at 400 metres and the sea breezes that sweep inland through the Gernika estuary. Here, clay soils lie on fragmented limestone rock, locally known as cayuela, allowing the vines’ roots to penetrate deep into the ground.

Hondarrabi Zuria is the dominant variety, followed by Hondarrabi Zuri Zerratia, with small amounts of Hondarrabi Beltza and international varieties originally planted on an experimental basis, including Riesling, Sauvignon Blanc and Chardonnay.

The wines are produced in a garage winery in the Gametxo neighbourhood of Ibarrangelu. Its informal but wonderfully situated tasting room is an open-air viewpoint with spectacular views over the coast and the island of Izaro.

The vineyards

Hasiberriak's story illustrates the challenges of organic farming in a region with high rainfall and humidity, as well as the importance of producing high-value wines capable of offseting the high production costs.

Initial production of 15,000 bottles was eventually reduced to just 3,000 as the duo struggled to control fungal diseasesand pests. This led them to abandon organic farming in the Mendata vineyard in 2025, the site that had suffered the greatest  losses, while continuing organically on the left bank, where the sun reaches the vines early in the morning and moisture disperses quickly. The change is expected to push production back  above 10,000 bottles from the 2026 vintage onwards.

Vineyard work is increasingly focused on soil regeneration and nourishing the vines through the use of fermented products. "It's very difficult here for grapes to get to the winery in super healthy condition," Gabantxo explains. Another concern in the area is the need to limit the use of copper in vineyards. The project has also expanded by a further hectare: a vineyard planted by Gabantxo in Lumo, just below Errigoiti, with Hondarrabi Beltza and Gros Manseng (known as Izkiriota in Basque).

The wines

As for the wines, 2022 was the final vintage of their entry-level txakoli, Mempe. The current range consists of three whites, each with an increasingly distinctive character, presented in Burgundy-shaped bottles, and a sparkling wine. A wide range of fermentation and ageing vessels is used, including stainless steel, amphorae, flexitanks, oak and chestnut barrels. In the winery, the aim is to press whole bunches, rely on spontaneous fermentation and bottle the wines without fining or filtration.

All the wines are named after traditional crafts and occupations in the area. The range begins with Nekazari (€20), meaning farmer. Aged in amphorae and stainless steel, it is a vibrant white offering a precise sense of place, with lively acidity and salty notes. Arotz (€28), meaning cabinet maker, is aged in oak, although chestnut is increasingly replacing French oak. It is a serious white, with less txakoli character but plenty of depth and length. The most limited cuvées, with fewer than 1,000 bottles available, are Baserritar (€35, farmhouse dweller), a wine that is aged under a layer of yeast to give a finely focused expression marked by the region's characteristic vibrant acidity; and Saregin (€45), an ancestral sparkling wine that showcases the region's excellent potential for producing Atlantic-style fizz. Its name is a tribute to the women who traditionally mended fishing nets in port areas.